From 986b42703815c96c2da3f26d5c5a126837fe4017 Mon Sep 17 00:00:00 2001
From: Jonathan Turner <jonathandturner@users.noreply.github.com>
Date: Mon, 7 Sep 2020 12:12:55 +1200
Subject: [PATCH] Add modulo operator and simplify in/not-in (#2505)

---
 crates/nu-cli/src/evaluate/operator.rs   |  8 ++++++++
 crates/nu-cli/tests/commands/math/mod.rs | 12 ++++++++++++
 crates/nu-cli/tests/commands/merge.rs    |  2 +-
 crates/nu-cli/tests/commands/where_.rs   |  4 ++--
 crates/nu-data/src/value.rs              |  7 +++++++
 crates/nu-parser/src/parse.rs            |  5 +++--
 crates/nu-protocol/src/hir.rs            |  3 ++-
 7 files changed, 35 insertions(+), 6 deletions(-)

diff --git a/crates/nu-cli/src/evaluate/operator.rs b/crates/nu-cli/src/evaluate/operator.rs
index c5bfee949..a1584999f 100644
--- a/crates/nu-cli/src/evaluate/operator.rs
+++ b/crates/nu-cli/src/evaluate/operator.rs
@@ -33,6 +33,14 @@ pub fn apply_operator(
             )),
             _ => res,
         }),
+        Operator::Modulo => value::compute_values(op, left, right).map(|res| match res {
+            UntaggedValue::Error(_) => UntaggedValue::Error(ShellError::labeled_error(
+                "Evaluation error",
+                "division by zero",
+                &right.tag.span,
+            )),
+            _ => res,
+        }),
         Operator::In => table_contains(left, right).map(UntaggedValue::boolean),
         Operator::NotIn => table_contains(left, right).map(|x| UntaggedValue::boolean(!x)),
         Operator::And => match (left.as_bool(), right.as_bool()) {
diff --git a/crates/nu-cli/tests/commands/math/mod.rs b/crates/nu-cli/tests/commands/math/mod.rs
index 2db1fbe56..36ecaf55c 100644
--- a/crates/nu-cli/tests/commands/math/mod.rs
+++ b/crates/nu-cli/tests/commands/math/mod.rs
@@ -161,6 +161,18 @@ fn parens_precedence() {
     assert_eq!(actual.out, "12");
 }
 
+#[test]
+fn modulo() {
+    let actual = nu!(
+        cwd: "tests/fixtures/formats", pipeline(
+        r#"
+            = 9 mod 2
+        "#
+    ));
+
+    assert_eq!(actual.out, "1");
+}
+
 #[test]
 fn duration_math() {
     let actual = nu!(
diff --git a/crates/nu-cli/tests/commands/merge.rs b/crates/nu-cli/tests/commands/merge.rs
index cda5a9178..52d48fb76 100644
--- a/crates/nu-cli/tests/commands/merge.rs
+++ b/crates/nu-cli/tests/commands/merge.rs
@@ -31,7 +31,7 @@ fn row() {
             r#"
                 open caballeros.csv
                 | merge { open new_caballeros.csv }
-                | where country in: ["Guayaquil Ecuador" "New Zealand"]
+                | where country in ["Guayaquil Ecuador" "New Zealand"]
                 | get luck
                 | math sum
                 | echo $it
diff --git a/crates/nu-cli/tests/commands/where_.rs b/crates/nu-cli/tests/commands/where_.rs
index b8979ee9b..9f6b1b88e 100644
--- a/crates/nu-cli/tests/commands/where_.rs
+++ b/crates/nu-cli/tests/commands/where_.rs
@@ -27,7 +27,7 @@ fn filters_with_nothing_comparison() {
 fn where_in_table() {
     let actual = nu!(
         cwd: "tests/fixtures/formats",
-        r#"echo '[{"name": "foo", "size": 3}, {"name": "foo", "size": 2}, {"name": "bar", "size": 4}]' | from json | where name in: ["foo"] | get size | math sum | echo $it"#
+        r#"echo '[{"name": "foo", "size": 3}, {"name": "foo", "size": 2}, {"name": "bar", "size": 4}]' | from json | where name in ["foo"] | get size | math sum | echo $it"#
     );
 
     assert_eq!(actual.out, "5");
@@ -37,7 +37,7 @@ fn where_in_table() {
 fn where_not_in_table() {
     let actual = nu!(
         cwd: "tests/fixtures/formats",
-        r#"echo '[{"name": "foo", "size": 3}, {"name": "foo", "size": 2}, {"name": "bar", "size": 4}]' | from json | where name not-in: ["foo"] | get size | math sum | echo $it"#
+        r#"echo '[{"name": "foo", "size": 3}, {"name": "foo", "size": 2}, {"name": "bar", "size": 4}]' | from json | where name not-in ["foo"] | get size | math sum | echo $it"#
     );
 
     assert_eq!(actual.out, "4");
diff --git a/crates/nu-data/src/value.rs b/crates/nu-data/src/value.rs
index 292140ecb..eecc2e9fa 100644
--- a/crates/nu-data/src/value.rs
+++ b/crates/nu-data/src/value.rs
@@ -131,6 +131,13 @@ pub fn compute_values(
                         )))
                     }
                 }
+                Operator::Modulo => {
+                    if y.is_zero() {
+                        Ok(zero_division_error())
+                    } else {
+                        Ok(UntaggedValue::Primitive(Primitive::Int(x % y)))
+                    }
+                }
                 _ => Err((left.type_name(), right.type_name())),
             },
             (Primitive::Decimal(x), Primitive::Int(y)) => {
diff --git a/crates/nu-parser/src/parse.rs b/crates/nu-parser/src/parse.rs
index 0beff84e6..b05878761 100644
--- a/crates/nu-parser/src/parse.rs
+++ b/crates/nu-parser/src/parse.rs
@@ -286,8 +286,9 @@ fn parse_operator(lite_arg: &Spanned<String>) -> (SpannedExpression, Option<Pars
         "-" => Operator::Minus,
         "*" => Operator::Multiply,
         "/" => Operator::Divide,
-        "in:" => Operator::In,
-        "not-in:" => Operator::NotIn,
+        "in" => Operator::In,
+        "not-in" => Operator::NotIn,
+        "mod" => Operator::Modulo,
         "&&" => Operator::And,
         "||" => Operator::Or,
         _ => {
diff --git a/crates/nu-protocol/src/hir.rs b/crates/nu-protocol/src/hir.rs
index 71dd4f53e..a164b36f3 100644
--- a/crates/nu-protocol/src/hir.rs
+++ b/crates/nu-protocol/src/hir.rs
@@ -575,7 +575,7 @@ impl SpannedExpression {
                 // Higher precedence binds tighter
 
                 match operator {
-                    Operator::Multiply | Operator::Divide => 100,
+                    Operator::Multiply | Operator::Divide | Operator::Modulo => 100,
                     Operator::Plus | Operator::Minus => 90,
                     Operator::NotContains
                     | Operator::Contains
@@ -848,6 +848,7 @@ pub enum Operator {
     Divide,
     In,
     NotIn,
+    Modulo,
     And,
     Or,
 }