From cb6ccc3c5a42f54801e2509d1f8c803faf168f5d Mon Sep 17 00:00:00 2001
From: Jason Gedge <jason.gedge@shopify.com>
Date: Mon, 25 May 2020 14:19:49 -0400
Subject: [PATCH] Improve the simplified parse form. (#1875)

---
 crates/nu-cli/tests/commands/parse.rs | 80 +++++++++++++++++++--------
 crates/nu_plugin_parse/src/nu/mod.rs  | 19 +++++--
 2 files changed, 71 insertions(+), 28 deletions(-)

diff --git a/crates/nu-cli/tests/commands/parse.rs b/crates/nu-cli/tests/commands/parse.rs
index aa14faf62..5c0754329 100644
--- a/crates/nu-cli/tests/commands/parse.rs
+++ b/crates/nu-cli/tests/commands/parse.rs
@@ -2,31 +2,67 @@ use nu_test_support::fs::Stub;
 use nu_test_support::playground::Playground;
 use nu_test_support::{nu, pipeline};
 
-#[test]
-fn extracts_fields_from_the_given_the_pattern() {
-    Playground::setup("parse_test_1", |dirs, sandbox| {
-        sandbox.with_files(vec![Stub::FileWithContentToBeTrimmed(
-            "key_value_separated_arepa_ingredients.txt",
-            r#"
-                VAR1=Cheese
-                VAR2=JonathanParsed
-                VAR3=NushellSecretIngredient
-            "#,
-        )]);
+mod simple {
+    use super::*;
 
-        let actual = nu!(
-            cwd: dirs.test(), pipeline(
-            r#"
-                open key_value_separated_arepa_ingredients.txt
-                | parse "{Name}={Value}"
-                | nth 1
-                | get Value
-                | echo $it
+    #[test]
+    fn extracts_fields_from_the_given_the_pattern() {
+        Playground::setup("parse_test_1", |dirs, sandbox| {
+            sandbox.with_files(vec![Stub::FileWithContentToBeTrimmed(
+                "key_value_separated_arepa_ingredients.txt",
+                r#"
+                    VAR1=Cheese
+                    VAR2=JonathanParsed
+                    VAR3=NushellSecretIngredient
+                "#,
+            )]);
+
+            let actual = nu!(
+                cwd: dirs.test(), pipeline(
+                r#"
+                    open key_value_separated_arepa_ingredients.txt
+                    | lines
+                    | each { echo $it | parse "{Name}={Value}" }
+                    | nth 1
+                    | echo $it.Value
+                "#
+            ));
+
+            assert_eq!(actual.out, "JonathanParsed");
+        })
+    }
+
+    #[test]
+    fn double_open_curly_evalutes_to_a_single_curly() {
+        Playground::setup("parse_test_regex_2", |dirs, _sandbox| {
+            let actual = nu!(
+                cwd: dirs.test(), pipeline(
+                r#"
+                echo "{abc}123"
+                | parse "{{abc}{name}"
+                | echo $it.name
             "#
-        ));
+            ));
 
-        assert_eq!(actual.out, "JonathanParsed");
-    })
+            assert_eq!(actual.out, "123");
+        })
+    }
+
+    #[test]
+    fn properly_escapes_text() {
+        Playground::setup("parse_test_regex_3", |dirs, _sandbox| {
+            let actual = nu!(
+                cwd: dirs.test(), pipeline(
+                r#"
+                echo "(abc)123"
+                | parse "(abc){name}"
+                | echo $it.name
+            "#
+            ));
+
+            assert_eq!(actual.out, "123");
+        })
+    }
 }
 
 mod regex {
diff --git a/crates/nu_plugin_parse/src/nu/mod.rs b/crates/nu_plugin_parse/src/nu/mod.rs
index 90ba204e1..b12c50541 100644
--- a/crates/nu_plugin_parse/src/nu/mod.rs
+++ b/crates/nu_plugin_parse/src/nu/mod.rs
@@ -6,7 +6,7 @@ use nu_protocol::{
 };
 
 use crate::{ColumnNames, Parse};
-use regex::Regex;
+use regex::{self, Regex};
 
 impl Plugin for Parse {
     fn config(&mut self) -> Result<Signature, ShellError> {
@@ -125,13 +125,18 @@ fn parse(input: &str) -> Vec<ParseCommand> {
     let mut output = vec![];
 
     //let mut loop_input = input;
-    let mut loop_input = input.chars();
+    let mut loop_input = input.chars().peekable();
     loop {
         let mut before = String::new();
 
         while let Some(c) = loop_input.next() {
             if c == '{' {
-                break;
+                // If '{{', still creating a plaintext parse command, but just for a single '{' char
+                if loop_input.peek() == Some(&'{') {
+                    let _ = loop_input.next();
+                } else {
+                    break;
+                }
             }
             before.push(c);
         }
@@ -188,19 +193,21 @@ impl From<&Regex> for ColumnNames {
 }
 
 fn build_regex(commands: &[ParseCommand]) -> String {
-    let mut output = String::new();
+    let mut output = "(?s)\\A".to_string();
 
     for command in commands {
         match command {
             ParseCommand::Text(s) => {
-                output.push_str(&s.replace("(", "\\("));
+                output.push_str(&regex::escape(&s));
             }
             ParseCommand::Column(_) => {
-                output.push_str("(.*)");
+                output.push_str("(.*?)");
             }
         }
     }
 
+    output.push_str("\\z");
+
     output
 }