From 55fb1f8dda641a6e45b40add5c92c97facd7d3a6 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Andr=C3=A9s=20N=2E=20Robalino?= <andres@androbtech.com>
Date: Wed, 28 Aug 2019 19:32:42 -0500
Subject: [PATCH] Yo quiero Playground taconushell.

---
 tests/command_cd_tests.rs    |   6 +-
 tests/command_cp_tests.rs    |  29 ++-
 tests/command_enter_test.rs  |  11 +-
 tests/command_ls_tests.rs    |  78 ++++---
 tests/command_mkdir_tests.rs |   8 +-
 tests/command_mv_tests.rs    |  74 +++----
 tests/command_open_tests.rs  |  92 +++++----
 tests/command_rm_tests.rs    | 117 +++++------
 tests/commands_test.rs       |  26 ++-
 tests/external_tests.rs      |   4 +-
 tests/filter_inc_tests.rs    | 172 ++++++++--------
 tests/filter_str_tests.rs    | 191 ++++++++++-------
 tests/filters_test.rs        | 387 ++++++++++++++++++++++-------------
 tests/helpers/mod.rs         |  43 ++--
 14 files changed, 698 insertions(+), 540 deletions(-)

diff --git a/tests/command_cd_tests.rs b/tests/command_cd_tests.rs
index e65775d46..932484e59 100644
--- a/tests/command_cd_tests.rs
+++ b/tests/command_cd_tests.rs
@@ -4,8 +4,8 @@ use helpers::in_directory as cwd;
 
 #[test]
 fn cd_directory_not_found() {
-    let output = nu_error!(cwd("tests/fixtures"), "cd dir_that_does_not_exist");
+    let actual = nu_error!(cwd("tests/fixtures"), "cd dir_that_does_not_exist");
 
-    assert!(output.contains("dir_that_does_not_exist"));
-    assert!(output.contains("directory not found"));
+    assert!(actual.contains("dir_that_does_not_exist"));
+    assert!(actual.contains("directory not found"));
 }
diff --git a/tests/command_cp_tests.rs b/tests/command_cp_tests.rs
index 9e7c37082..e41c24d1c 100644
--- a/tests/command_cp_tests.rs
+++ b/tests/command_cp_tests.rs
@@ -1,7 +1,6 @@
 mod helpers;
 
-use helpers::{dir_exists_at, file_exists_at, files_exist_at, Playground, Stub::*};
-
+use helpers::{in_directory as cwd, dir_exists_at, file_exists_at, files_exist_at, Playground, Stub::*};
 use nu::AbsoluteFile;
 use std::path::{Path, PathBuf};
 
@@ -9,7 +8,7 @@ use std::path::{Path, PathBuf};
 fn copies_a_file() {
     Playground::setup("cp_test_1", |dirs, _| {
         nu!(
-            dirs.root(),
+            cwd(dirs.root()),
             "cp {} cp_test_1/sample.ini",
             dirs.formats().join("sample.ini")
         );
@@ -24,7 +23,7 @@ fn copies_the_file_inside_directory_if_path_to_copy_is_directory() {
         let expected_file = AbsoluteFile::new(dirs.test().join("sample.ini"));
 
         nu!(
-            dirs.formats(),
+            cwd(dirs.formats()),
             "cp ../formats/sample.ini {}",
             expected_file.dir()
         );
@@ -36,17 +35,17 @@ fn copies_the_file_inside_directory_if_path_to_copy_is_directory() {
 #[test]
 fn error_if_attempting_to_copy_a_directory_to_another_directory() {
     Playground::setup("cp_test_3", |dirs, _| {
-        let output = nu_error!(dirs.formats(), "cp ../formats {}", dirs.test());
+        let actual = nu_error!(dirs.formats(), "cp ../formats {}", dirs.test());
 
-        assert!(output.contains("../formats"));
-        assert!(output.contains("is a directory (not copied)"));
+        assert!(actual.contains("../formats"));
+        assert!(actual.contains("is a directory (not copied)"));
     });
 }
 
 #[test]
 fn copies_the_directory_inside_directory_if_path_to_copy_is_directory_and_with_recursive_flag() {
-    Playground::setup("cp_test_4", |dirs, playground| {
-        playground
+    Playground::setup("cp_test_4", |dirs, sandbox| {
+        sandbox
             .within("originals")
             .with_files(vec![
                 EmptyFile("yehuda.txt"),
@@ -57,7 +56,7 @@ fn copies_the_directory_inside_directory_if_path_to_copy_is_directory_and_with_r
 
         let expected_dir = dirs.test().join("expected").join("originals");
 
-        nu!(dirs.test(), "cp originals expected --recursive");
+        nu!(cwd(dirs.test()), "cp originals expected --recursive");
 
         assert!(dir_exists_at(PathBuf::from(&expected_dir)));
         assert!(files_exist_at(
@@ -91,8 +90,8 @@ fn deep_copies_with_recursive_flag() {
         originals/contributors/yehuda/defer-evaluation.txt
     "#;
 
-    Playground::setup("cp_test_5", |dirs, playground| {
-        playground
+    Playground::setup("cp_test_5", |dirs, sandbox| {
+        sandbox
             .within("originals")
             .with_files(vec![EmptyFile("manifest.txt")])
             .within("originals/contributors")
@@ -115,7 +114,7 @@ fn deep_copies_with_recursive_flag() {
         let andres_expected_copied_dir = expected_dir.join("contributors").join("andres");
         let yehudas_expected_copied_dir = expected_dir.join("contributors").join("yehuda");
 
-        nu!(dirs.test(), "cp originals expected --recursive");
+        nu!(cwd(dirs.test()), "cp originals expected --recursive");
 
         assert!(dir_exists_at(PathBuf::from(&expected_dir)));
         assert!(files_exist_at(
@@ -136,7 +135,7 @@ fn deep_copies_with_recursive_flag() {
 #[test]
 fn copies_using_path_with_wildcard() {
     Playground::setup("cp_test_6", |dirs, _| {
-        nu!(dirs.formats(), "cp ../formats/* {}", dirs.test());
+        nu!(cwd(dirs.formats()), "cp ../formats/* {}", dirs.test());
 
         assert!(files_exist_at(
             vec![
@@ -155,7 +154,7 @@ fn copies_using_path_with_wildcard() {
 #[test]
 fn copies_using_a_glob() {
     Playground::setup("cp_test_7", |dirs, _| {
-        nu!(dirs.formats(), "cp * {}", dirs.test());
+        nu!(cwd(dirs.formats()), "cp * {}", dirs.test());
 
         assert!(files_exist_at(
             vec![
diff --git a/tests/command_enter_test.rs b/tests/command_enter_test.rs
index a204655b7..61a7441df 100644
--- a/tests/command_enter_test.rs
+++ b/tests/command_enter_test.rs
@@ -1,13 +1,13 @@
 mod helpers;
 
-use h::{Playground, Stub::*};
+use h::{in_directory as cwd, Playground, Stub::*};
 use helpers as h;
 use std::path::{Path, PathBuf};
 
 #[test]
 fn knows_the_filesystems_entered() {
-    Playground::setup("enter_filesystem_sessions_test", |dirs, playground| {
-        playground
+    Playground::setup("enter_test_1", |dirs, sandbox| {
+        sandbox
             .within("red_pill")
             .with_files(vec![
                 EmptyFile("andres.nu"),
@@ -20,8 +20,7 @@ fn knows_the_filesystems_entered() {
                 EmptyFile("korn.nxt"),
                 EmptyFile("powedsh.nxt"),
             ])
-            .mkdir("expected")
-            .test_dir_name();
+            .mkdir("expected");
 
         let red_pill_dir = dirs.test().join("red_pill");
         let blue_pill_dir = dirs.test().join("blue_pill");
@@ -29,7 +28,7 @@ fn knows_the_filesystems_entered() {
         let expected_recycled = expected.join("recycled");
 
         nu!(
-            dirs.test(),
+            cwd(dirs.test()),
             r#"
             enter expected
             mkdir recycled
diff --git a/tests/command_ls_tests.rs b/tests/command_ls_tests.rs
index 9b3d637ee..0f1bc8b7d 100644
--- a/tests/command_ls_tests.rs
+++ b/tests/command_ls_tests.rs
@@ -5,62 +5,86 @@ use helpers as h;
 
 #[test]
 fn ls_lists_regular_files() {
-    Playground::setup("ls_lists_files_test", |dirs, playground| {
-        playground
+    Playground::setup("ls_test_1", |dirs, sandbox| {
+        sandbox
             .with_files(vec![
                 EmptyFile("yehuda.10.txt"),
                 EmptyFile("jonathan.10.txt"),
                 EmptyFile("andres.10.txt"),
-            ])
-            .test_dir_name();
+        ]);
 
-        let output = nu!(
-            dirs.test(),
-            r#"ls | get name | lines | split-column "." | get Column2 | str --to-int | sum | echo $it"#
-        );
+        let actual = nu!(
+            cwd(dirs.test()), h::pipeline(
+                r#"
+                    ls 
+                    | get name 
+                    | lines 
+                    | split-column "." 
+                    | get Column2 
+                    | str --to-int 
+                    | sum 
+                    | echo $it
+                "#
+        ));
 
-        assert_eq!(output, "30");
+        assert_eq!(actual, "30");
     })
 }
 
 #[test]
 fn ls_lists_regular_files_using_asterisk_wildcard() {
-    Playground::setup("ls_asterisk_wildcard_test", |dirs, playground| {
-        playground
+    Playground::setup("ls_test_2", |dirs, sandbox| {
+        sandbox
             .with_files(vec![
                 EmptyFile("los.1.txt"),
                 EmptyFile("tres.1.txt"),
                 EmptyFile("amigos.1.txt"),
                 EmptyFile("arepas.1.clu"),
-            ])
-            .test_dir_name();
+        ]);
 
-        let output = nu!(
-            dirs.test(),
-            r#"ls *.txt | get name | lines| split-column "." | get Column2 | str --to-int | sum | echo $it"#
-        );
+        let actual = nu!(
+            cwd(dirs.test()), h::pipeline(
+                r#"
+                    ls *.txt 
+                    | get name 
+                    | lines 
+                    | split-column "." 
+                    | get Column2 
+                    | str --to-int 
+                    | sum 
+                    | echo $it
+                "#
+        ));
 
-        assert_eq!(output, "3");
+        assert_eq!(actual, "3");
     })
 }
 
 #[test]
 fn ls_lists_regular_files_using_question_mark_wildcard() {
-    Playground::setup("ls_question_mark_wildcard_test", |dirs, playground| {
-        playground
+    Playground::setup("ls_test_3", |dirs, sandbox| {
+        sandbox
             .with_files(vec![
                 EmptyFile("yehuda.10.txt"),
                 EmptyFile("jonathan.10.txt"),
                 EmptyFile("andres.10.txt"),
                 EmptyFile("chicken_not_to_be_picked_up.100.txt"),
-            ])
-            .test_dir_name();
+        ]);
 
-        let output = nu!(
-        dirs.test(),
-        r#"ls *.??.txt | get name | lines| split-column "." | get Column2 | str --to-int | sum | echo $it"#
-    );
+        let actual = nu!(
+            cwd(dirs.test()), h::pipeline(
+                r#"
+                    ls *.??.txt 
+                    | get name 
+                    | lines 
+                    | split-column "." 
+                    | get Column2 
+                    | str --to-int 
+                    | sum 
+                    | echo $it
+                "#
+        ));
 
-        assert_eq!(output, "30");
+        assert_eq!(actual, "30");
     })
 }
diff --git a/tests/command_mkdir_tests.rs b/tests/command_mkdir_tests.rs
index d62fb6ac9..192349ae0 100644
--- a/tests/command_mkdir_tests.rs
+++ b/tests/command_mkdir_tests.rs
@@ -1,13 +1,13 @@
 mod helpers;
 
-use h::Playground;
+use h::{in_directory as cwd, Playground};
 use helpers as h;
 use std::path::{Path, PathBuf};
 
 #[test]
 fn creates_directory() {
     Playground::setup("mkdir_test_1", |dirs, _| {
-        nu!(dirs.test(), "mkdir my_new_directory");
+        nu!(cwd(dirs.test()), "mkdir my_new_directory");
 
         let expected = dirs.test().join("my_new_directory");
 
@@ -18,7 +18,7 @@ fn creates_directory() {
 #[test]
 fn accepts_and_creates_directories() {
     Playground::setup("mkdir_test_2", |dirs, _| {
-        nu!(dirs.test(), "mkdir dir_1 dir_2 dir_3");
+        nu!(cwd(dirs.test()), "mkdir dir_1 dir_2 dir_3");
 
         assert!(h::files_exist_at(
             vec![Path::new("dir_1"), Path::new("dir_2"), Path::new("dir_3")],
@@ -30,7 +30,7 @@ fn accepts_and_creates_directories() {
 #[test]
 fn creates_intermediary_directories() {
     Playground::setup("mkdir_test_3", |dirs, _| {
-        nu!(dirs.test(), "mkdir some_folder/another/deeper_one");
+        nu!(cwd(dirs.test()), "mkdir some_folder/another/deeper_one");
 
         let mut expected = PathBuf::from(dirs.test());
         expected.push("some_folder/another/deeper_one");
diff --git a/tests/command_mv_tests.rs b/tests/command_mv_tests.rs
index aee6ff1e6..7fa70495e 100644
--- a/tests/command_mv_tests.rs
+++ b/tests/command_mv_tests.rs
@@ -3,20 +3,17 @@ mod helpers;
 use h::{in_directory as cwd, Playground, Stub::*};
 use helpers as h;
 
-use std::path::{Path, PathBuf};
-
 #[test]
 fn moves_a_file() {
-    Playground::setup("mv_test_1", |dirs, playground| {
-        playground
+    Playground::setup("mv_test_1", |dirs, sandbox| {
+        sandbox
             .with_files(vec![EmptyFile("andres.txt")])
-            .mkdir("expected")
-            .test_dir_name();
+            .mkdir("expected");
 
         let original = dirs.test().join("andres.txt");
         let expected = dirs.test().join("expected/yehuda.txt");
 
-        nu!(dirs.test(), "mv andres.txt expected/yehuda.txt");
+        nu!(cwd(dirs.test()), "mv andres.txt expected/yehuda.txt");
 
         assert!(!h::file_exists_at(original));
         assert!(h::file_exists_at(expected));
@@ -25,15 +22,17 @@ fn moves_a_file() {
 
 #[test]
 fn overwrites_if_moving_to_existing_file() {
-    Playground::setup("mv_test_2", |dirs, playground| {
-        playground
-            .with_files(vec![EmptyFile("andres.txt"), EmptyFile("jonathan.txt")])
-            .test_dir_name();
+    Playground::setup("mv_test_2", |dirs, sandbox| {
+        sandbox
+            .with_files(vec![
+                EmptyFile("andres.txt"), 
+                EmptyFile("jonathan.txt")
+        ]);
 
         let original = dirs.test().join("andres.txt");
         let expected = dirs.test().join("jonathan.txt");
 
-        nu!(dirs.test(), "mv andres.txt jonathan.txt");
+        nu!(cwd(dirs.test()), "mv andres.txt jonathan.txt");
 
         assert!(!h::file_exists_at(original));
         assert!(h::file_exists_at(expected));
@@ -42,13 +41,13 @@ fn overwrites_if_moving_to_existing_file() {
 
 #[test]
 fn moves_a_directory() {
-    Playground::setup("mv_test_3", |dirs, playground| {
-        playground.mkdir("empty_dir");
+    Playground::setup("mv_test_3", |dirs, sandbox| {
+        sandbox.mkdir("empty_dir");
 
         let original_dir = dirs.test().join("empty_dir");
         let expected = dirs.test().join("renamed_dir");
 
-        nu!(dirs.test(), "mv empty_dir renamed_dir");
+        nu!(cwd(dirs.test()), "mv empty_dir renamed_dir");
 
         assert!(!h::dir_exists_at(original_dir));
         assert!(h::dir_exists_at(expected));
@@ -57,11 +56,10 @@ fn moves_a_directory() {
 
 #[test]
 fn moves_the_file_inside_directory_if_path_to_move_is_existing_directory() {
-    Playground::setup("mv_test_4", |dirs, playground| {
-        playground
+    Playground::setup("mv_test_4", |dirs, sandbox| {
+        sandbox
             .with_files(vec![EmptyFile("jonathan.txt")])
-            .mkdir("expected")
-            .test_dir_name();
+            .mkdir("expected");
 
         let original_dir = dirs.test().join("jonathan.txt");
         let expected = dirs.test().join("expected/jonathan.txt");
@@ -75,12 +73,11 @@ fn moves_the_file_inside_directory_if_path_to_move_is_existing_directory() {
 
 #[test]
 fn moves_the_directory_inside_directory_if_path_to_move_is_existing_directory() {
-    Playground::setup("mv_test_5", |dirs, playground| {
-        playground
+    Playground::setup("mv_test_5", |dirs, sandbox| {
+        sandbox
             .within("contributors")
             .with_files(vec![EmptyFile("jonathan.txt")])
-            .mkdir("expected")
-            .test_dir_name();
+            .mkdir("expected");
 
         let original_dir = dirs.test().join("contributors");
         let expected = dirs.test().join("expected/contributors");
@@ -94,17 +91,16 @@ fn moves_the_directory_inside_directory_if_path_to_move_is_existing_directory()
 
 #[test]
 fn moves_the_directory_inside_directory_if_path_to_move_is_nonexistent_directory() {
-    Playground::setup("mv_test_6", |dirs, playground| {
-        playground
+    Playground::setup("mv_test_6", |dirs, sandbox| {
+        sandbox
             .within("contributors")
             .with_files(vec![EmptyFile("jonathan.txt")])
-            .mkdir("expected")
-            .test_dir_name();
+            .mkdir("expected");
 
         let original_dir = dirs.test().join("contributors");
 
         nu!(
-            dirs.test(),
+            cwd(dirs.test()),
             "mv contributors expected/this_dir_exists_now/los_tres_amigos"
         );
 
@@ -119,8 +115,8 @@ fn moves_the_directory_inside_directory_if_path_to_move_is_nonexistent_directory
 
 #[test]
 fn moves_using_path_with_wildcard() {
-    Playground::setup("mv_test_7", |dirs, playground| {
-        playground
+    Playground::setup("mv_test_7", |dirs, sandbox| {
+        sandbox
             .within("originals")
             .with_files(vec![
                 EmptyFile("andres.ini"),
@@ -131,16 +127,15 @@ fn moves_using_path_with_wildcard() {
                 EmptyFile("sgml_description.json"),
                 EmptyFile("sample.ini"),
                 EmptyFile("utf16.ini"),
-                EmptyFile("yehuda.ini"),
+                EmptyFile("yehuda.ini")
             ])
             .mkdir("work_dir")
-            .mkdir("expected")
-            .test_dir_name();
+            .mkdir("expected");
 
         let work_dir = dirs.test().join("work_dir");
         let expected = dirs.test().join("expected");
 
-        nu!(work_dir, "mv ../originals/*.ini ../expected");
+        nu!(cwd(work_dir), "mv ../originals/*.ini ../expected");
 
         assert!(h::files_exist_at(
             vec!["yehuda.ini", "jonathan.ini", "sample.ini", "andres.ini",],
@@ -151,23 +146,22 @@ fn moves_using_path_with_wildcard() {
 
 #[test]
 fn moves_using_a_glob() {
-    Playground::setup("mv_test_8", |dirs, playground| {
-        playground
+    Playground::setup("mv_test_8", |dirs, sandbox| {
+        sandbox
             .within("meals")
             .with_files(vec![
                 EmptyFile("arepa.txt"),
                 EmptyFile("empanada.txt"),
-                EmptyFile("taquiza.txt"),
+                EmptyFile("taquiza.txt")
             ])
             .mkdir("work_dir")
-            .mkdir("expected")
-            .test_dir_name();
+            .mkdir("expected");
 
         let meal_dir = dirs.test().join("meals");
         let work_dir = dirs.test().join("work_dir");
         let expected = dirs.test().join("expected");
 
-        nu!(work_dir, "mv ../meals/* ../expected");
+        nu!(cwd(work_dir), "mv ../meals/* ../expected");
 
         assert!(h::dir_exists_at(meal_dir));
         assert!(h::files_exist_at(
diff --git a/tests/command_open_tests.rs b/tests/command_open_tests.rs
index 7835316f1..4824936c2 100644
--- a/tests/command_open_tests.rs
+++ b/tests/command_open_tests.rs
@@ -1,106 +1,126 @@
 mod helpers;
 
 use helpers::{in_directory as cwd, Playground, Stub::*};
+use helpers as h;
 
 #[test]
 fn recognizes_csv() {
-    Playground::setup_for("open_recognizes_csv_test").with_files(vec![FileWithContentToBeTrimmed(
-        "nu.zion.csv",
-        r#"
-            author,lang,source
-            Jonathan Turner,Rust,New Zealand
-            Andres N. Robalino,Rust,Ecuador
-            Yehuda Katz,Rust,Estados Unidos
-        "#,
-    )]);
+    Playground::setup("open_test_1", |dirs, sandbox| {
+        sandbox
+            .with_files(vec![FileWithContentToBeTrimmed(
+                "nu.zion.csv",
+                r#"
+                    author,lang,source
+                    Jonathan Turner,Rust,New Zealand
+                    Andres N. Robalino,Rust,Ecuador
+                    Yehuda Katz,Rust,Estados Unidos
+                "#
+        )]);
 
-    let output = nu!(
-        cwd("tests/fixtures/nuplayground/open_recognizes_csv_test"),
-        r#"open nu.zion.csv | where author == "Andres N. Robalino" | get source | echo $it"#
-    );
+        let actual = nu!(
+            cwd(dirs.test()), h::pipeline(
+            r#"
+                open nu.zion.csv 
+                | where author == "Andres N. Robalino" 
+                | get source 
+                | echo $it
+            "#
+        ));
 
-    assert_eq!(output, "Ecuador");
+        assert_eq!(actual, "Ecuador");
+    })
 }
 
 #[test]
 fn open_can_parse_bson_1() {
-    let output = nu!(
+    let actual = nu!(
         cwd("tests/fixtures/formats"),
         "open sample.bson | get root | nth 0 | get b | echo $it"
     );
 
-    assert_eq!(output, "hello");
+    assert_eq!(actual, "hello");
 }
 
 #[test]
 fn open_can_parse_bson_2() {
-    let output = nu!(
-        cwd("tests/fixtures/formats"),
-        "open sample.bson | get root | nth 6 | get b | get '$binary_subtype' | echo $it "
-    );
+    let actual = nu!(
+        cwd("tests/fixtures/formats"), h::pipeline(
+            r#"
+                open sample.bson 
+                | get root 
+                | nth 6 
+                | get b 
+                | get '$binary_subtype' 
+                | echo $it
+            "#
+        ));
 
-    assert_eq!(output, "function");
+    assert_eq!(actual, "function");
 }
 
 #[test]
 fn open_can_parse_toml() {
-    let output = nu!(
+    let actual = nu!(
         cwd("tests/fixtures/formats"),
         "open cargo_sample.toml | get package.edition | echo $it"
     );
 
-    assert_eq!(output, "2018");
+    assert_eq!(actual, "2018");
 }
 
 #[test]
 fn open_can_parse_json() {
-    let output = nu!(
-        cwd("tests/fixtures/formats"),
-        "open sgml_description.json | get glossary.GlossDiv.GlossList.GlossEntry.GlossSee | echo $it"
-    );
+    let actual = nu!(
+        cwd("tests/fixtures/formats"), h::pipeline(
+        r#"
+            open sgml_description.json 
+            | get glossary.GlossDiv.GlossList.GlossEntry.GlossSee 
+            | echo $it
+        "#
+    ));
 
-    assert_eq!(output, "markup")
+    assert_eq!(actual, "markup")
 }
 
 #[test]
 fn open_can_parse_xml() {
-    let output = nu!(
+    let actual = nu!(
         cwd("tests/fixtures/formats"),
         "open jonathan.xml | get rss.channel.item.link | echo $it"
     );
 
     assert_eq!(
-        output,
+        actual,
         "http://www.jonathanturner.org/2015/10/off-to-new-adventures.html"
     )
 }
 
 #[test]
 fn open_can_parse_ini() {
-    let output = nu!(
+    let actual = nu!(
         cwd("tests/fixtures/formats"),
         "open sample.ini | get SectionOne.integer | echo $it"
     );
 
-    assert_eq!(output, "1234")
+    assert_eq!(actual, "1234")
 }
 
 #[test]
 fn open_can_parse_utf16_ini() {
-    let output = nu!(
+    let actual = nu!(
         cwd("tests/fixtures/formats"),
         "open utf16.ini | get .ShellClassInfo | get IconIndex | echo $it"
     );
 
-    assert_eq!(output, "-236")
+    assert_eq!(actual, "-236")
 }
 
 #[test]
 fn errors_if_file_not_found() {
-    let output = nu_error!(
+    let actual = nu_error!(
         cwd("tests/fixtures/formats"),
         "open i_dont_exist.txt | echo $it"
     );
 
-    assert!(output.contains("File could not be opened"));
+    assert!(actual.contains("File could not be opened"));
 }
diff --git a/tests/command_rm_tests.rs b/tests/command_rm_tests.rs
index 1e8553548..2d5a90e8d 100644
--- a/tests/command_rm_tests.rs
+++ b/tests/command_rm_tests.rs
@@ -2,16 +2,15 @@ mod helpers;
 
 use h::{in_directory as cwd, Playground, Stub::*};
 use helpers as h;
-use std::path::{Path, PathBuf};
 
 #[test]
 fn rm_removes_a_file() {
-    Playground::setup("rm_regular_file_test", |dirs, playground| {
-        playground
-            .with_files(vec![EmptyFile("i_will_be_deleted.txt")])
-            .test_dir_name();
+    Playground::setup("rm_test_1", |dirs, sandbox| {
+        sandbox
+            .with_files(vec![EmptyFile("i_will_be_deleted.txt")
+        ]);
 
-        nu!(dirs.root(), "rm rm_regular_file_test/i_will_be_deleted.txt");
+        nu!(cwd(dirs.root()), "rm rm_test_1/i_will_be_deleted.txt");
 
         let path = dirs.test().join("i_will_be_deleted.txt");
 
@@ -21,13 +20,13 @@ fn rm_removes_a_file() {
 
 #[test]
 fn rm_removes_files_with_wildcard() {
-    Playground::setup("rm_wildcard_test_1", |dirs, playground| {
-        playground
+    Playground::setup("rm_test_2", |dirs, sandbox| {
+        sandbox
             .within("src")
             .with_files(vec![
                 EmptyFile("cli.rs"),
                 EmptyFile("lib.rs"),
-                EmptyFile("prelude.rs"),
+                EmptyFile("prelude.rs")
             ])
             .within("src/parser")
             .with_files(vec![EmptyFile("parse.rs"), EmptyFile("parser.rs")])
@@ -36,11 +35,10 @@ fn rm_removes_files_with_wildcard() {
             .within("src/parser/hir")
             .with_files(vec![
                 EmptyFile("baseline_parse.rs"),
-                EmptyFile("baseline_parse_tokens.rs"),
-            ])
-            .test_dir_name();
+                EmptyFile("baseline_parse_tokens.rs")
+        ]);
 
-        nu!(dirs.test(), r#"rm "src/*/*/*.rs""#);
+        nu!(cwd(dirs.test()), r#"rm "src/*/*/*.rs""#);
 
         assert!(!h::files_exist_at(
             vec![
@@ -53,20 +51,20 @@ fn rm_removes_files_with_wildcard() {
 
         assert_eq!(
             Playground::glob_vec(&format!("{}/src/*/*/*.rs", dirs.test().display())),
-            Vec::<PathBuf>::new()
+            Vec::<std::path::PathBuf>::new()
         );
     })
 }
 
 #[test]
 fn rm_removes_deeply_nested_directories_with_wildcard_and_recursive_flag() {
-    Playground::setup("rm_wildcard_test_2", |dirs, playground| {
-        playground
+    Playground::setup("rm_test_3", |dirs, sandbox| {
+        sandbox
             .within("src")
             .with_files(vec![
                 EmptyFile("cli.rs"),
                 EmptyFile("lib.rs"),
-                EmptyFile("prelude.rs"),
+                EmptyFile("prelude.rs")
             ])
             .within("src/parser")
             .with_files(vec![EmptyFile("parse.rs"), EmptyFile("parser.rs")])
@@ -75,11 +73,10 @@ fn rm_removes_deeply_nested_directories_with_wildcard_and_recursive_flag() {
             .within("src/parser/hir")
             .with_files(vec![
                 EmptyFile("baseline_parse.rs"),
-                EmptyFile("baseline_parse_tokens.rs"),
-            ])
-            .test_dir_name();
+                EmptyFile("baseline_parse_tokens.rs")
+        ]);
 
-        nu!(dirs.test(), "rm src/* --recursive");
+        nu!(cwd(dirs.test()), "rm src/* --recursive");
 
         assert!(!h::files_exist_at(
             vec!["src/parser/parse", "src/parser/hir"],
@@ -90,8 +87,8 @@ fn rm_removes_deeply_nested_directories_with_wildcard_and_recursive_flag() {
 
 #[test]
 fn rm_removes_directory_contents_without_recursive_flag_if_empty() {
-    Playground::setup("rm_directory_removal_recursively_test_1", |dirs, _| {
-        nu!(dirs.root(), "rm rm_directory_removal_recursively_test_1");
+    Playground::setup("rm_test_4", |dirs, _| {
+        nu!(cwd(dirs.root()), "rm rm_test_4");
 
         assert!(!h::file_exists_at(dirs.test()));
     })
@@ -99,67 +96,51 @@ fn rm_removes_directory_contents_without_recursive_flag_if_empty() {
 
 #[test]
 fn rm_removes_directory_contents_with_recursive_flag() {
-    Playground::setup(
-        "rm_directory_removal_recursively_test_2",
-        |dirs, playground| {
-            playground
-                .with_files(vec![
-                    EmptyFile("yehuda.txt"),
-                    EmptyFile("jonathan.txt"),
-                    EmptyFile("andres.txt"),
-                ])
-                .test_dir_name();
+    Playground::setup("rm_test_5", |dirs, sandbox| {
+        sandbox
+            .with_files(vec![
+                EmptyFile("yehuda.txt"),
+                EmptyFile("jonathan.txt"),
+                EmptyFile("andres.txt")
+        ]);
 
-            nu!(
-                dirs.root(),
-                "rm rm_directory_removal_recursively_test_2 --recursive"
-            );
+        nu!(cwd(dirs.root()), "rm rm_test_5 --recursive");
 
-            assert!(!h::file_exists_at(dirs.test()));
-        },
-    )
+        assert!(!h::file_exists_at(dirs.test()));
+    })
 }
 
 #[test]
 fn rm_errors_if_attempting_to_delete_a_directory_with_content_without_recursive_flag() {
-    Playground::setup(
-        "rm_prevent_directory_removal_without_flag_test",
-        |dirs, playground| {
-            playground
-                .with_files(vec![EmptyFile("some_empty_file.txt")])
-                .test_dir_name();
+    Playground::setup("rm_test_6", |dirs, sandbox| {
+        sandbox
+            .with_files(vec![EmptyFile("some_empty_file.txt")
+        ]);
 
-            let output = nu_error!(
-                dirs.root(),
-                "rm rm_prevent_directory_removal_without_flag_test"
-            );
+        let actual = nu_error!(
+            cwd(dirs.root()),
+            "rm rm_test_6"
+        );
 
-            assert!(h::file_exists_at(dirs.test()));
-            assert!(output.contains("is a directory"));
-        },
-    )
+        assert!(h::file_exists_at(dirs.test()));
+        assert!(actual.contains("is a directory"));
+    })
 }
 
 #[test]
 fn rm_errors_if_attempting_to_delete_single_dot_as_argument() {
-    Playground::setup(
-        "rm_errors_if_attempting_to_delete_single_dot_as_argument",
-        |dirs, _| {
-            let output = nu_error!(dirs.root(), "rm .");
+    Playground::setup("rm_test_7", |dirs, _| {
+        let actual = nu_error!(cwd(dirs.root()), "rm .");
 
-            assert!(output.contains("may not be removed"));
-        },
-    )
+        assert!(actual.contains("may not be removed"));
+    })
 }
 
 #[test]
 fn rm_errors_if_attempting_to_delete_two_dot_as_argument() {
-    Playground::setup(
-        "rm_errors_if_attempting_to_delete_single_dot_as_argument",
-        |dirs, _| {
-            let output = nu_error!(dirs.root(), "rm ..");
+    Playground::setup("rm_test_8", |dirs, _| {
+        let actual = nu_error!(cwd(dirs.root()), "rm ..");
 
-            assert!(output.contains("may not be removed"));
-        },
-    )
+        assert!(actual.contains("may not be removed"));
+    })
 }
diff --git a/tests/commands_test.rs b/tests/commands_test.rs
index 9b131256b..6384581c9 100644
--- a/tests/commands_test.rs
+++ b/tests/commands_test.rs
@@ -5,21 +5,20 @@ use helpers as h;
 
 #[test]
 fn lines() {
-    let output = nu!(
+    let actual = nu!(
         cwd("tests/fixtures/formats"),
         r#"open cargo_sample.toml --raw | lines | skip-while $it != "[dependencies]" | skip 1 | first 1 | split-column "=" | get Column1 | trim | echo $it"#
     );
 
-    assert_eq!(output, "rustyline");
+    assert_eq!(actual, "rustyline");
 }
 
 #[test]
 fn save_figures_out_intelligently_where_to_write_out_with_metadata() {
-    Playground::setup("save_smart_test", |dirs, playground| {
-        playground
-            .with_files(vec![FileWithContent(
-                "cargo_sample.toml",
-                r#"
+    Playground::setup("save_test_1", |dirs, sandbox| {
+        sandbox.with_files(vec![FileWithContent(
+            "cargo_sample.toml",
+            r#"
                 [package]
                 name = "nu"
                 version = "0.1.1"
@@ -27,15 +26,14 @@ fn save_figures_out_intelligently_where_to_write_out_with_metadata() {
                 description = "A shell for the GitHub era"
                 license = "ISC"
                 edition = "2018"
-            "#,
-            )])
-            .test_dir_name();
+            "#)
+        ]);
 
         let subject_file = dirs.test().join("cargo_sample.toml");
 
         nu!(
-            dirs.root(),
-            "open save_smart_test/cargo_sample.toml | inc package.version --minor | save"
+            cwd(dirs.root()),
+            "open save_test_1/cargo_sample.toml | inc package.version --minor | save"
         );
 
         let actual = h::file_contents(&subject_file);
@@ -45,12 +43,12 @@ fn save_figures_out_intelligently_where_to_write_out_with_metadata() {
 
 #[test]
 fn save_can_write_out_csv() {
-    Playground::setup("save_writes_out_csv_test", |dirs, playground| {
+    Playground::setup("save_test_2", |dirs, _| {
         let expected_file = dirs.test().join("cargo_sample.csv");
 
         nu!(
             dirs.root(),
-            "open {}/cargo_sample.toml | inc package.version --minor | get package | save save_writes_out_csv_test/cargo_sample.csv",
+            "open {}/cargo_sample.toml | inc package.version --minor | get package | save save_test_2/cargo_sample.csv",
             dirs.formats()
         );
 
diff --git a/tests/external_tests.rs b/tests/external_tests.rs
index d98319301..6e1d2eec7 100644
--- a/tests/external_tests.rs
+++ b/tests/external_tests.rs
@@ -4,7 +4,7 @@ use helpers::in_directory as cwd;
 
 #[test]
 fn external_command() {
-    let output = nu!(cwd("tests/fixtures"), "echo 1");
+    let actual = nu!(cwd("tests/fixtures"), "echo 1");
 
-    assert!(output.contains("1"));
+    assert!(actual.contains("1"));
 }
diff --git a/tests/filter_inc_tests.rs b/tests/filter_inc_tests.rs
index 9a4722543..6ba98e554 100644
--- a/tests/filter_inc_tests.rs
+++ b/tests/filter_inc_tests.rs
@@ -5,124 +5,136 @@ use helpers as h;
 
 #[test]
 fn can_only_apply_one() {
-    let output = nu_error!(
+    let actual = nu_error!(
         cwd("tests/fixtures/formats"),
         "open cargo_sample.toml | first 1 | inc package.version --major --minor"
     );
 
-    assert!(output.contains("Usage: inc field [--major|--minor|--patch]"));
+    assert!(actual.contains("Usage: inc field [--major|--minor|--patch]"));
 }
 
 #[test]
 fn by_one_with_field_passed() {
-    Playground::setup_for("plugin_inc_by_one_with_field_passed_test").with_files(vec![
-        FileWithContent(
-            "sample.toml",
-            r#"
-                [package]
-                edition = "2018"
-            "#,
-        ),
-    ]);
+    Playground::setup("plugin_inc_test_1", |dirs, sandbox| {
+        sandbox
+            .with_files(vec![FileWithContent(
+                "sample.toml",
+                r#"
+                    [package]
+                    edition = "2018"
+                "#
+        )]);
 
-    let output = nu!(
-        cwd("tests/fixtures/nuplayground/plugin_inc_by_one_with_field_passed_test"),
-        "open sample.toml | inc package.edition | get package.edition | echo $it"
-    );
+        let actual = nu!(
+            cwd(dirs.test()),
+            "open sample.toml | inc package.edition | get package.edition | echo $it"
+        );
 
-    assert_eq!(output, "2019");
+        assert_eq!(actual, "2019");
+    })
 }
 
 #[test]
 fn by_one_with_no_field_passed() {
-    Playground::setup_for("plugin_inc_by_one_with_no_field_passed_test").with_files(vec![
-        FileWithContent(
-            "sample.toml",
-            r#"
-                [package]
-                contributors = "2"
-            "#,
-        ),
-    ]);
+    Playground::setup("plugin_inc_test_2", |dirs, sandbox| {
+        sandbox
+            .with_files(vec![FileWithContent(
+                "sample.toml",
+                r#"
+                    [package]
+                    contributors = "2"
+                "#
+        )]);
 
-    let output = nu!(
-        cwd("tests/fixtures/nuplayground/plugin_inc_by_one_with_no_field_passed_test"),
-        "open sample.toml | get package.contributors | inc | echo $it"
-    );
+        let actual = nu!(
+            cwd(dirs.test()),
+            "open sample.toml | get package.contributors | inc | echo $it"
+        );
 
-    assert_eq!(output, "3");
+        assert_eq!(actual, "3");
+    })
 }
 
 #[test]
 fn semversion_major_inc() {
-    Playground::setup_for("plugin_inc_major_semversion_test").with_files(vec![FileWithContent(
-        "sample.toml",
-        r#"
-                [package]
-                version = "0.1.3"
-            "#,
-    )]);
+    Playground::setup("plugin_inc_test_3", |dirs, sandbox| {
+        sandbox
+            .with_files(vec![FileWithContent(
+                "sample.toml",
+                r#"
+                    [package]
+                    version = "0.1.3"
+                "#
+        )]);
 
-    let output = nu!(
-        cwd("tests/fixtures/nuplayground/plugin_inc_major_semversion_test"),
-        "open sample.toml | inc package.version --major | get package.version | echo $it"
-    );
+        let actual = nu!(
+            cwd(dirs.test()),
+            "open sample.toml | inc package.version --major | get package.version | echo $it"
+        );
 
-    assert_eq!(output, "1.0.0");
+        assert_eq!(actual, "1.0.0");
+    })
 }
 
 #[test]
 fn semversion_minor_inc() {
-    Playground::setup_for("plugin_inc_minor_semversion_test").with_files(vec![FileWithContent(
-        "sample.toml",
-        r#"
-                [package]
-                version = "0.1.3"
-            "#,
-    )]);
+    Playground::setup("plugin_inc_test_4", |dirs, sandbox| {
+        sandbox
+            .with_files(vec![FileWithContent(
+                "sample.toml",
+                r#"
+                    [package]
+                    version = "0.1.3"
+                "#
+        )]);
 
-    let output = nu!(
-        cwd("tests/fixtures/nuplayground/plugin_inc_minor_semversion_test"),
-        "open sample.toml | inc package.version --minor | get package.version | echo $it"
-    );
+        let actual = nu!(
+            cwd(dirs.test()),
+            "open sample.toml | inc package.version --minor | get package.version | echo $it"
+        );
 
-    assert_eq!(output, "0.2.0");
+        assert_eq!(actual, "0.2.0");
+    })
 }
 
 #[test]
 fn semversion_patch_inc() {
-    Playground::setup_for("plugin_inc_patch_semversion_test").with_files(vec![FileWithContent(
-        "sample.toml",
-        r#"
-                [package]
-                version = "0.1.3"
-            "#,
-    )]);
+    Playground::setup("plugin_inc_test_5", |dirs, sandbox| {
+        sandbox
+            .with_files(vec![FileWithContent(
+                "sample.toml",
+                r#"
+                    [package]
+                    version = "0.1.3"
+                "#
+        )]);
 
-    let output = nu!(
-        cwd("tests/fixtures/nuplayground/plugin_inc_patch_semversion_test"),
-        "open sample.toml | inc package.version --patch | get package.version | echo $it"
-    );
+        let actual = nu!(
+            cwd(dirs.test()),
+            "open sample.toml | inc package.version --patch | get package.version | echo $it"
+        );
 
-    assert_eq!(output, "0.1.4");
+        assert_eq!(actual, "0.1.4");
+    })
 }
 
 #[test]
 fn semversion_without_passing_field() {
-    Playground::setup_for("plugin_inc_semversion_without_passing_field_test").with_files(vec![
-        FileWithContent(
-            "sample.toml",
-            r#"
-                [package]
-                version = "0.1.3"
-            "#,
-        ),
-    ]);
+    Playground::setup("plugin_inc_test_6", |dirs, sandbox| {
+        sandbox
+            .with_files(vec![FileWithContent(
+                "sample.toml",
+                r#"
+                    [package]
+                    version = "0.1.3"
+                "#
+        )]);
 
-    let output = nu!(
-        cwd("tests/fixtures/nuplayground/plugin_inc_semversion_without_passing_field_test"),
-        "open sample.toml | get package.version | inc --patch | echo $it"
-    );
+        let actual = nu!(
+            cwd(dirs.test()),
+            "open sample.toml | get package.version | inc --patch | echo $it"
+        );
 
-    assert_eq!(output, "0.1.4");
+        assert_eq!(actual, "0.1.4");
+    })
 }
diff --git a/tests/filter_str_tests.rs b/tests/filter_str_tests.rs
index 7bb377369..7774f9dcf 100644
--- a/tests/filter_str_tests.rs
+++ b/tests/filter_str_tests.rs
@@ -5,135 +5,170 @@ use helpers as h;
 
 #[test]
 fn can_only_apply_one() {
-    let output = nu_error!(
+    let actual = nu_error!(
         cwd("tests/fixtures/formats"),
         "open caco3_plastics.csv | first 1 | str origin --downcase --upcase"
     );
 
     assert!(
-        output.contains("Usage: str field [--downcase|--upcase|--to-int|--replace|--find-replace]")
+        actual.contains("Usage: str field [--downcase|--upcase|--to-int|--replace|--find-replace]")
     );
 }
 
 #[test]
 fn acts_without_passing_field() {
-    Playground::setup_for("plugin_str_acts_without_passing_field_test").with_files(vec![
-        FileWithContent(
+    Playground::setup("plugin_str_test_1", |dirs, sandbox| {
+        sandbox.with_files(vec![FileWithContent(
             "sample.yml",
             r#"
                 environment:
                   global:
                     PROJECT_NAME: nushell
             "#,
-        ),
-    ]);
+        )]);
 
-    let output = nu!(
-        cwd("tests/fixtures/nuplayground/plugin_str_acts_without_passing_field_test"),
-        "open sample.yml | get environment.global.PROJECT_NAME | str --upcase | echo $it"
-    );
+        let actual = nu!(
+            cwd(dirs.test()),
+            "open sample.yml | get environment.global.PROJECT_NAME | str --upcase | echo $it"
+        );
 
-    assert_eq!(output, "NUSHELL");
+        assert_eq!(actual, "NUSHELL");
+    })
 }
 
 #[test]
 fn downcases() {
-    Playground::setup_for("plugin_str_downcases_test").with_files(vec![FileWithContent(
-        "sample.toml",
-        r#"
-            [dependency]
-            name = "LIGHT"
-        "#,
-    )]);
+    Playground::setup("plugin_str_test_2", |dirs, sandbox| {
+        sandbox
+            .with_files(vec![FileWithContent(
+                "sample.toml",
+                r#"
+                    [dependency]
+                    name = "LIGHT"
+                "#,
+        )]);
 
-    let output = nu!(
-        cwd("tests/fixtures/nuplayground/plugin_str_downcases_test"),
-        "open sample.toml | str dependency.name --downcase | get dependency.name | echo $it"
-    );
+        let actual = nu!(
+            cwd(dirs.test()),
+            "open sample.toml | str dependency.name --downcase | get dependency.name | echo $it"
+        );
 
-    assert_eq!(output, "light");
+        assert_eq!(actual, "light");
+    })
 }
 
 #[test]
 fn upcases() {
-    Playground::setup_for("plugin_str_upcases_test").with_files(vec![FileWithContent(
-        "sample.toml",
-        r#"
-            [package]
-            name = "nushell"
-        "#,
-    )]);
+    Playground::setup("plugin_str_test_3", |dirs, sandbox| {
+        sandbox
+            .with_files(vec![FileWithContent(
+                "sample.toml",
+                r#"
+                    [package]
+                    name = "nushell"
+                "#,
+        )]);
 
-    let output = nu!(
-        cwd("tests/fixtures/nuplayground/plugin_str_upcases_test"),
-        "open sample.toml | str package.name --upcase | get package.name | echo $it"
-    );
-
-    assert_eq!(output, "NUSHELL");
+        let actual = nu!(
+            cwd(dirs.test()),
+            "open sample.toml | str package.name --upcase | get package.name | echo $it"
+        );
+    
+        assert_eq!(actual, "NUSHELL");
+    })
 }
 
 #[test]
 fn converts_to_int() {
-    let output = nu!(
-        cwd("tests/fixtures/formats"),
-        "open caco3_plastics.csv | first 1 | str tariff_item --to-int | where tariff_item == 2509000000 | get tariff_item | echo $it"
-    );
+    let actual = nu!(
+        cwd("tests/fixtures/formats"), h::pipeline(
+            r#"
+                open caco3_plastics.csv 
+                | first 1 
+                | str tariff_item --to-int 
+                | where tariff_item == 2509000000 
+                | get tariff_item 
+                | echo $it
+            "#
+    ));
 
-    assert_eq!(output, "2509000000");
+    assert_eq!(actual, "2509000000");
 }
 
 #[test]
 fn replaces() {
-    Playground::setup_for("plugin_str_replaces_test").with_files(vec![FileWithContent(
-        "sample.toml",
-        r#"
-            [package]
-            name = "nushell"
-        "#,
-    )]);
+    Playground::setup("plugin_str_test_4", |dirs, sandbox| {
+        sandbox
+            .with_files(vec![FileWithContent(
+                "sample.toml",
+                r#"
+                    [package]
+                    name = "nushell"
+                "#,
+        )]);
 
-    let output = nu!(
-        cwd("tests/fixtures/nuplayground/plugin_str_replaces_test"),
-        "open sample.toml | str package.name --replace wykittenshell  | get package.name | echo $it"
-    );
+        let actual = nu!(
+            cwd(dirs.test()), h::pipeline(
+            r#"
+                open sample.toml 
+                | str package.name --replace wykittenshell  
+                | get package.name 
+                | echo $it
+            "#
+        ));
 
-    assert_eq!(output, "wykittenshell");
+        assert_eq!(actual, "wykittenshell");
+    })
 }
 
 #[test]
 fn find_and_replaces() {
-    Playground::setup_for("plugin_str_find_and_replaces_test").with_files(vec![FileWithContent(
-        "sample.toml",
-        r#"
-            [fortune.teller]
-            phone = "1-800-KATZ"
-        "#,
-    )]);
+    Playground::setup("plugin_str_test_5", |dirs, sandbox| {
+        sandbox
+            .with_files(vec![FileWithContent(
+                "sample.toml",
+                r#"
+                    [fortune.teller]
+                    phone = "1-800-KATZ"
+                "#,
+        )]);
 
-    let output = nu!(
-        cwd("tests/fixtures/nuplayground/plugin_str_find_and_replaces_test"),
-        r#"open sample.toml | str fortune.teller.phone --find-replace KATZ "5289" | get fortune.teller.phone | echo $it"#
-    );
+        let actual = nu!(
+            cwd(dirs.test()), h::pipeline(
+            r#"
+                open sample.toml 
+                | str fortune.teller.phone --find-replace KATZ "5289" 
+                | get fortune.teller.phone 
+                | echo $it
+            "#
+        ));
 
-    assert_eq!(output, "1-800-5289");
+        assert_eq!(actual, "1-800-5289");
+    })
 }
 
 #[test]
 fn find_and_replaces_without_passing_field() {
-    Playground::setup_for("plugin_str_find_and_replaces_without_passing_field_test").with_files(
-        vec![FileWithContent(
+    Playground::setup("plugin_str_test_6", |dirs, sandbox| {
+        sandbox
+            .with_files(vec![FileWithContent(
             "sample.toml",
+                r#"
+                    [fortune.teller]
+                    phone = "1-800-KATZ"
+                "#,
+        )]);
+
+        let actual = nu!(
+            cwd(dirs.test()), h::pipeline(
             r#"
-                [fortune.teller]
-                phone = "1-800-KATZ"
-            "#,
-        )],
-    );
+                open sample.toml 
+                | get fortune.teller.phone 
+                | str --find-replace KATZ "5289" 
+                | echo $it
+            "#
+        ));
 
-    let output = nu!(
-        cwd("tests/fixtures/nuplayground/plugin_str_find_and_replaces_without_passing_field_test"),
-        r#"open sample.toml | get fortune.teller.phone | str --find-replace KATZ "5289" | echo $it"#
-    );
-
-    assert_eq!(output, "1-800-5289");
+        assert_eq!(actual, "1-800-5289");
+    })
 }
diff --git a/tests/filters_test.rs b/tests/filters_test.rs
index 191e6e30b..3fb4dbd00 100644
--- a/tests/filters_test.rs
+++ b/tests/filters_test.rs
@@ -1,263 +1,360 @@
 mod helpers;
 
 use helpers::{in_directory as cwd, Playground, Stub::*};
+use helpers as h;
 
 #[test]
 fn can_convert_table_to_csv_text_and_from_csv_text_back_into_table() {
-    let output = nu!(
+    let actual = nu!(
         cwd("tests/fixtures/formats"),
         "open caco3_plastics.csv | to-csv | from-csv | first 1 | get origin | echo $it"
     );
 
-    assert_eq!(output, "SPAIN");
+    assert_eq!(actual, "SPAIN");
 }
 
 #[test]
 fn converts_structured_table_to_csv_text() {
-    Playground::setup_for("filter_to_csv_test_1").with_files(vec![FileWithContentToBeTrimmed(
-        "sample.txt",
-        r#"
-            importer,shipper,tariff_item,name,origin
-            Plasticos Rival,Reverte,2509000000,Calcium carbonate,Spain
-            Tigre Ecuador,OMYA Andina,3824909999,Calcium carbonate,Colombia
-        "#,
-    )]);
+    Playground::setup("filter_to_csv_test_1", |dirs, sandbox| {
+        sandbox
+            .with_files(vec![FileWithContentToBeTrimmed(
+                "csv_text_sample.txt",
+                r#"
+                    importer,shipper,tariff_item,name,origin
+                    Plasticos Rival,Reverte,2509000000,Calcium carbonate,Spain
+                    Tigre Ecuador,OMYA Andina,3824909999,Calcium carbonate,Colombia
+                "#
+        )]);
 
-    let output = nu!(
-        cwd("tests/fixtures/nuplayground/filter_to_csv_test_1"),
-        r#"open sample.txt | lines | split-column "," a b c d origin  | last 1 | to-csv | lines | nth 1 | echo "$it""#
-    );
+        let actual = nu!(
+            cwd(dirs.test()), h::pipeline(
+            r#"
+                open csv_text_sample.txt 
+                | lines 
+                | split-column "," a b c d origin  
+                | last 1 
+                | to-csv 
+                | lines 
+                | nth 1 
+                | echo "$it"
+            "#
+        ));
 
-    assert!(output.contains("Tigre Ecuador,OMYA Andina,3824909999,Calcium carbonate,Colombia"));
+        assert!(actual.contains("Tigre Ecuador,OMYA Andina,3824909999,Calcium carbonate,Colombia"));
+    })
 }
 
 #[test]
 fn converts_structured_table_to_csv_text_skipping_headers_after_conversion() {
-    Playground::setup_for("filter_to_csv_test_2").with_files(vec![FileWithContentToBeTrimmed(
-        "sample.txt",
-        r#"
-            importer,shipper,tariff_item,name,origin
-            Plasticos Rival,Reverte,2509000000,Calcium carbonate,Spain
-            Tigre Ecuador,OMYA Andina,3824909999,Calcium carbonate,Colombia
-        "#,
-    )]);
+    Playground::setup("filter_to_csv_test_2", |dirs, sandbox| {
+        sandbox
+            .with_files(vec![FileWithContentToBeTrimmed(
+                "csv_text_sample.txt",
+                r#"
+                    importer,shipper,tariff_item,name,origin
+                    Plasticos Rival,Reverte,2509000000,Calcium carbonate,Spain
+                    Tigre Ecuador,OMYA Andina,3824909999,Calcium carbonate,Colombia
+                "#
+        )]);
 
-    let output = nu!(
-        cwd("tests/fixtures/nuplayground/filter_to_csv_test_2"),
-        r#"open sample.txt | lines | split-column "," a b c d origin  | last 1 | to-csv --headerless | echo "$it""#
-    );
+        let actual = nu!(
+            cwd(dirs.test()), h::pipeline(
+            r#"
+                open csv_text_sample.txt 
+                | lines 
+                | split-column "," a b c d origin  
+                | last 1 
+                | to-csv --headerless 
+                | echo "$it"
+            "#
+        ));
 
-    assert!(output.contains("Tigre Ecuador,OMYA Andina,3824909999,Calcium carbonate,Colombia"));
+        assert!(actual.contains("Tigre Ecuador,OMYA Andina,3824909999,Calcium carbonate,Colombia"));
+    })
 }
 
 #[test]
 fn converts_from_csv_text_to_structured_table() {
-    Playground::setup_for("filter_from_csv_test_1").with_files(vec![FileWithContentToBeTrimmed(
-        "los_tres_amigos.txt",
-        r#"
-            first_name,last_name,rusty_luck
-            Andrés,Robalino,1
-            Jonathan,Turner,1
-            Yehuda,Katz,1
-        "#,
-    )]);
+    Playground::setup("filter_from_csv_test_1", |dirs, sandbox| {
+        sandbox
+            .with_files(vec![FileWithContentToBeTrimmed(
+                "los_tres_amigos.txt",
+                r#"
+                    first_name,last_name,rusty_luck
+                    Andrés,Robalino,1
+                    Jonathan,Turner,1
+                    Yehuda,Katz,1
+                "#,
+        )]);
 
-    let output = nu!(
-        cwd("tests/fixtures/nuplayground/filter_from_csv_test_1"),
-        "open los_tres_amigos.txt | from-csv | get rusty_luck | str --to-int | sum | echo $it"
-    );
+        let actual = nu!(
+            cwd(dirs.test()), h::pipeline(
+            r#"
+                open los_tres_amigos.txt 
+                | from-csv 
+                | get rusty_luck 
+                | str --to-int 
+                | sum 
+                | echo "$it"
+            "#
+        ));
 
-    assert_eq!(output, "3");
+        assert_eq!(actual, "3");
+    })
 }
 
 #[test]
 fn converts_from_csv_text_skipping_headers_to_structured_table() {
-    Playground::setup_for("filter_from_csv_test_2").with_files(vec![FileWithContentToBeTrimmed(
-        "los_tres_amigos.txt",
-        r#"
-            first_name,last_name,rusty_luck
-            Andrés,Robalino,1
-            Jonathan,Turner,1
-            Yehuda,Katz,1
-        "#,
-    )]);
+    Playground::setup("filter_from_csv_test_2", |dirs, sandbox| {
+        sandbox
+            .with_files(vec![FileWithContentToBeTrimmed(
+                "los_tres_amigos.txt",
+                r#"
+                    first_name,last_name,rusty_luck
+                    Andrés,Robalino,1
+                    Jonathan,Turner,1
+                    Yehuda,Katz,1
+                "#,
+        )]);
 
-    let output = nu!(
-        cwd("tests/fixtures/nuplayground/filter_from_csv_test_2"),
-        "open los_tres_amigos.txt | from-csv --headerless | get Column3 | str --to-int | sum | echo $it"
-    );
+        let actual = nu!(
+            cwd(dirs.test()), h::pipeline(
+            r#"
+                open los_tres_amigos.txt 
+                | from-csv --headerless 
+                | get Column3 
+                | str --to-int 
+                | sum 
+                | echo $it
+            "#
+        ));
 
-    assert_eq!(output, "3");
+        assert_eq!(actual, "3");
+    })
 }
 
 #[test]
 fn can_convert_table_to_json_text_and_from_json_text_back_into_table() {
-    let output = nu!(
-        cwd("tests/fixtures/formats"),
-        "open sgml_description.json | to-json | from-json | get glossary.GlossDiv.GlossList.GlossEntry.GlossSee | echo $it"
-    );
+    let actual = nu!(
+        cwd("tests/fixtures/formats"), h::pipeline(
+        r#"
+            open sgml_description.json 
+            | to-json 
+            | from-json 
+            | get glossary.GlossDiv.GlossList.GlossEntry.GlossSee 
+            | echo $it
+        "#
+    ));
 
-    assert_eq!(output, "markup");
+    assert_eq!(actual, "markup");
 }
 
 #[test]
 fn converts_from_json_text_to_structured_table() {
-    Playground::setup_for("filter_from_json_test_1").with_files(vec![FileWithContentToBeTrimmed(
-        "katz.txt",
-        r#"
-            {
-                "katz": [
-                    {"name":   "Yehuda", "rusty_luck": 1}, 
-                    {"name": "Jonathan", "rusty_luck": 1}, 
-                    {"name":   "Andres", "rusty_luck": 1},
-                    {"name":"GorbyPuff", "rusty_luck": 1}
-                ]
-            }
-        "#,
-    )]);
+    Playground::setup("filter_from_json_test_1", |dirs, sandbox| {
+        sandbox
+            .with_files(vec![FileWithContentToBeTrimmed(
+                "katz.txt",
+                r#"
+                    {
+                        "katz": [
+                            {"name":   "Yehuda", "rusty_luck": 1}, 
+                            {"name": "Jonathan", "rusty_luck": 1}, 
+                            {"name":   "Andres", "rusty_luck": 1},
+                            {"name":"GorbyPuff", "rusty_luck": 1}
+                        ]
+                    }
+                "#,
+        )]);
 
-    let output = nu!(
-        cwd("tests/fixtures/nuplayground/filter_from_json_test_1"),
-        "open katz.txt | from-json | get katz | get rusty_luck | sum | echo $it"
-    );
+        let actual = nu!(
+            cwd(dirs.test()),
+            "open katz.txt | from-json | get katz | get rusty_luck | sum | echo $it"
+        );
 
-    assert_eq!(output, "4");
+        assert_eq!(actual, "4");
+
+    })
 }
 
 #[test]
 fn converts_from_json_text_recognizing_objects_independendtly_to_structured_table() {
-    Playground::setup_for("filter_from_json_test_2").with_files(vec![FileWithContentToBeTrimmed(
-        "katz.txt",
-        r#"
-            {"name":   "Yehuda", "rusty_luck": 1} 
-            {"name": "Jonathan", "rusty_luck": 1} 
-            {"name":   "Andres", "rusty_luck": 1}
-            {"name":"GorbyPuff", "rusty_luck": 3}
-        "#,
-    )]);
+    Playground::setup("filter_from_json_test_2", |dirs, sandbox| {
+        sandbox
+            .with_files(vec![FileWithContentToBeTrimmed(
+                "katz.txt",
+                r#"
+                    {"name":   "Yehuda", "rusty_luck": 1} 
+                    {"name": "Jonathan", "rusty_luck": 1} 
+                    {"name":   "Andres", "rusty_luck": 1}
+                    {"name":"GorbyPuff", "rusty_luck": 3}
+                "#,
+        )]);
 
-    let output = nu!(
-        cwd("tests/fixtures/nuplayground/filter_from_json_test_2"),
-        r#"open katz.txt | from-json --objects | where name == "GorbyPuff" | get rusty_luck | echo $it"#
-    );
+        let actual = nu!(
+            cwd(dirs.test()), h::pipeline(
+            r#"
+                open katz.txt 
+                | from-json --objects 
+                | where name == "GorbyPuff" 
+                | get rusty_luck 
+                | echo $it
+            "#
+        ));
 
-    assert_eq!(output, "3");
+        assert_eq!(actual, "3");
+    })
 }
 
 #[test]
 fn converts_structured_table_to_json_text() {
-    Playground::setup_for("filter_to_json_test_1").with_files(vec![FileWithContentToBeTrimmed(
-        "sample.txt",
-        r#"
-            JonAndrehudaTZ,3
-            GorbyPuff,100
-        "#,
-    )]);
+    Playground::setup("filter_to_json_test", |dirs, sandbox| {
+        sandbox
+            .with_files(vec![FileWithContentToBeTrimmed(
+                "sample.txt",
+                r#"
+                    JonAndrehudaTZ,3
+                    GorbyPuff,100
+                "#,
+        )]);
 
-    let output = nu!(
-        cwd("tests/fixtures/nuplayground/filter_to_json_test_1"),
-        r#"open sample.txt | lines | split-column "," name luck | pick name | to-json | nth 0 | from-json | get name | echo $it"#
-    );
+        let actual = nu!(
+            cwd(dirs.test()), h::pipeline(
+            r#"
+                open sample.txt 
+                | lines 
+                | split-column "," name luck 
+                | pick name 
+                | to-json 
+                | nth 0 
+                | from-json 
+                | get name 
+                | echo $it
+            "#
+        ));
 
-    assert_eq!(output, "JonAndrehudaTZ");
+        assert_eq!(actual, "JonAndrehudaTZ");
+    })
 }
 
 #[test]
 fn can_convert_json_text_to_bson_and_back_into_table() {
-    let output = nu!(
+    let actual = nu!(
         cwd("tests/fixtures/formats"),
         "open sample.bson | to-bson | from-bson | get root | nth 1 | get b | echo $it"
     );
 
-    assert_eq!(output, "whel");
+    assert_eq!(actual, "whel");
 }
 
 #[test]
 fn can_convert_table_to_toml_text_and_from_toml_text_back_into_table() {
-    let output = nu!(
+    let actual = nu!(
         cwd("tests/fixtures/formats"),
         "open cargo_sample.toml | to-toml | from-toml | get package.name | echo $it"
     );
 
-    assert_eq!(output, "nu");
+    assert_eq!(actual, "nu");
 }
 
 #[test]
 fn can_convert_table_to_yaml_text_and_from_yaml_text_back_into_table() {
-    let output = nu!(
-        cwd("tests/fixtures/formats"),
-        "open appveyor.yml | to-yaml | from-yaml | get environment.global.PROJECT_NAME | echo $it"
-    );
+    let actual = nu!(
+        cwd("tests/fixtures/formats"), h::pipeline(
+        r#"
+            open appveyor.yml 
+            | to-yaml 
+            | from-yaml 
+            | get environment.global.PROJECT_NAME 
+            | echo $it
+        "#
+    ));
 
-    assert_eq!(output, "nushell");
+    assert_eq!(actual, "nushell");
 }
 
 #[test]
 fn can_sort_by_column() {
-    let output = nu!(
-        cwd("tests/fixtures/formats"),
-        r#"open cargo_sample.toml --raw | lines | skip 1 | first 4 | split-column "=" | sort-by Column1 | skip 1 | first 1 | get Column1 | trim | echo $it"#
-    );
+    let actual = nu!(
+        cwd("tests/fixtures/formats"), h::pipeline(
+        r#"
+            open cargo_sample.toml --raw 
+            | lines 
+            | skip 1 
+            | first 4 
+            | split-column "=" 
+            | sort-by Column1 
+            | skip 1 
+            | first 1 
+            | get Column1 
+            | trim 
+            | echo $it
+        "#
+    ));
 
-    assert_eq!(output, "description");
-}
-
-#[test]
-fn can_sort_by_column_reverse() {
-    let output = nu!(
-        cwd("tests/fixtures/formats"),
-        r#"open cargo_sample.toml --raw | lines | skip 1 | first 4 | split-column "=" | sort-by Column1 --reverse | skip 1 | first 1 | get Column1 | trim | echo $it"#
-    );
-
-    assert_eq!(output, "name");
+    assert_eq!(actual, "description");
 }
 
 #[test]
 fn can_split_by_column() {
-    let output = nu!(
-        cwd("tests/fixtures/formats"),
-        r#"open cargo_sample.toml --raw | lines | skip 1 | first 1 | split-column "=" | get Column1 | trim | echo $it"#
-    );
+    let actual = nu!(
+        cwd("tests/fixtures/formats"), h::pipeline(
+        r#"
+            open cargo_sample.toml --raw 
+            | lines 
+            | skip 1 
+            | first 1 
+            | split-column "=" 
+            | get Column1 
+            | trim 
+            | echo $it
+        "#
+    ));
 
-    assert_eq!(output, "name");
+    assert_eq!(actual, "name");
 }
 
 #[test]
 fn can_sum() {
-    let output = nu!(
-        cwd("tests/fixtures/formats"),
-        "open sgml_description.json | get glossary.GlossDiv.GlossList.GlossEntry.Sections | sum | echo $it"
-    );
+    let actual = nu!(
+        cwd("tests/fixtures/formats"), h::pipeline(
+        r#"
+            open sgml_description.json 
+            | get glossary.GlossDiv.GlossList.GlossEntry.Sections 
+            | sum 
+            | echo $it
+        "#
+    ));
 
-    assert_eq!(output, "203")
+    assert_eq!(actual, "203")
 }
 
 #[test]
 fn can_filter_by_unit_size_comparison() {
-    let output = nu!(
+    let actual = nu!(
         cwd("tests/fixtures/formats"),
         "ls | where size > 1kb | sort-by size | get name | skip 1 | trim | echo $it"
     );
 
-    assert_eq!(output, "caco3_plastics.csv");
+    assert_eq!(actual, "caco3_plastics.csv");
 }
 
 #[test]
 fn can_get_last() {
-    let output = nu!(
+    let actual = nu!(
         cwd("tests/fixtures/formats"),
         "ls | sort-by name | last 1 | get name | trim | echo $it"
     );
 
-    assert_eq!(output, "utf16.ini");
+    assert_eq!(actual, "utf16.ini");
 }
 
 #[test]
 fn can_get_reverse_first() {
-    let output = nu!(
+    let actual = nu!(
         cwd("tests/fixtures/formats"),
         "ls | sort-by name | reverse | first 1 | get name | trim | echo $it"
     );
 
-    assert_eq!(output, "utf16.ini");
+    assert_eq!(actual, "utf16.ini");
 }
diff --git a/tests/helpers/mod.rs b/tests/helpers/mod.rs
index 5009284c0..e8a4107a1 100644
--- a/tests/helpers/mod.rs
+++ b/tests/helpers/mod.rs
@@ -176,17 +176,26 @@ impl Playground {
         self.root.path()
     }
 
-    pub fn test_dir_name(&self) -> String {
-        self.tests.clone()
-    }
-
     pub fn back_to_playground(&mut self) -> &mut Self {
         self.cwd = PathBuf::from(self.root()).join(self.tests.clone());
         self
     }
 
     pub fn setup(topic: &str, block: impl FnOnce(Dirs, &mut Playground)) {
-        let mut playground = Playground::setup_for(topic);
+        let root = tempdir().expect("Couldn't create a tempdir");
+        let nuplay_dir = root.path().join(topic);
+
+        if PathBuf::from(&nuplay_dir).exists() {
+            std::fs::remove_dir_all(PathBuf::from(&nuplay_dir)).expect("can not remove directory");
+        }
+
+        std::fs::create_dir(PathBuf::from(&nuplay_dir)).expect("can not create directory");
+
+        let mut playground = Playground {
+            root: root,
+            tests: topic.to_string(),
+            cwd: nuplay_dir,
+        };
 
         let project_root = PathBuf::from(env!("CARGO_MANIFEST_DIR"));
         let playground_root = playground.root.path();
@@ -219,23 +228,6 @@ impl Playground {
         block(dirs, &mut playground);
     }
 
-    pub fn setup_for(topic: &str) -> Playground {
-        let root = tempdir().expect("Couldn't create a tempdir");
-        let nuplay_dir = root.path().join(topic);
-
-        if PathBuf::from(&nuplay_dir).exists() {
-            std::fs::remove_dir_all(PathBuf::from(&nuplay_dir)).expect("can not remove directory");
-        }
-
-        std::fs::create_dir(PathBuf::from(&nuplay_dir)).expect("can not create directory");
-
-        Playground {
-            root: root,
-            tests: topic.to_string(),
-            cwd: nuplay_dir,
-        }
-    }
-
     pub fn mkdir(&mut self, directory: &str) -> &mut Self {
         self.cwd.push(directory);
         std::fs::create_dir_all(&self.cwd).expect("can not create directory");
@@ -376,3 +368,10 @@ pub fn executable_path() -> PathBuf {
 pub fn in_directory(str: impl AsRef<Path>) -> String {
     str.as_ref().display().to_string()
 }
+
+pub fn pipeline(commands: &str) -> String {
+    commands.lines()
+            .skip(1)
+            .collect::<Vec<&str>>()
+            .concat()
+}