From a4811e8a500e7d8a61ac6c45f64ce6a994c014fa Mon Sep 17 00:00:00 2001
From: "Shahar \"Dawn\" Or" <mightyiampresence@gmail.com>
Date: Sat, 1 Jun 2024 16:47:35 +0200
Subject: [PATCH] test: some repl example unit tests

Co-authored-by: ruben beck <ruben.beck@pm.me>
Co-authored-by: Ishwar <ishwargowda100@gmail.com>
Co-authored-by: warren2k <846021+warren2k@users.noreply.github.com>
---
 Cargo.lock          |  23 ++++++++
 Cargo.toml          |   1 +
 src/repl/example.rs | 141 +++++++++++++++++++++++++++++++++++++++++++-
 3 files changed, 164 insertions(+), 1 deletion(-)

diff --git a/Cargo.lock b/Cargo.lock
index 91a2fff..3becfba 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -321,6 +321,12 @@ version = "0.4.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "850878694b7933ca4c9569d30a34b55031b9b139ee1fc7b94a527c4ef960d690"
 
+[[package]]
+name = "diff"
+version = "0.1.13"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "56254986775e3233ffa9c4d7d3faaf6d36a2c09d30b20687e9f88bc8bafc16c8"
+
 [[package]]
 name = "difflib"
 version = "0.4.0"
@@ -349,6 +355,7 @@ dependencies = [
  "indoc",
  "itertools",
  "predicates",
+ "pretty_assertions",
  "pty-process",
  "strip-ansi-escapes",
  "tokio",
@@ -836,6 +843,16 @@ dependencies = [
  "termtree",
 ]
 
+[[package]]
+name = "pretty_assertions"
+version = "1.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "af7cee1a6c8a5b9208b3cb1061f10c0cb689087b3d8ce85fb9d2dd7a29b6ba66"
+dependencies = [
+ "diff",
+ "yansi",
+]
+
 [[package]]
 name = "proc-macro2"
 version = "1.0.66"
@@ -1396,3 +1413,9 @@ checksum = "56c1936c4cc7a1c9ab21a1ebb602eb942ba868cbd44a99cb7cdc5892335e1c85"
 dependencies = [
  "linked-hash-map",
 ]
+
+[[package]]
+name = "yansi"
+version = "0.5.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "09041cd90cf85f7f8b2df60c646f853b7f535ce68f85244eb6731cf89fa498ec"
diff --git a/Cargo.toml b/Cargo.toml
index bd4eab9..762f06c 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -32,3 +32,4 @@ assert_cmd = "2.0.12"
 assert_fs = "1.0.13"
 indoc = "2.0.3"
 predicates = "3.1.0"
+pretty_assertions = "1.4.0"
diff --git a/src/repl/example.rs b/src/repl/example.rs
index a218cfb..86bee3b 100644
--- a/src/repl/example.rs
+++ b/src/repl/example.rs
@@ -83,7 +83,7 @@ impl std::str::FromStr for ReplExampleEntries {
     }
 }
 
-#[derive(Debug, Clone)]
+#[derive(Debug, Clone, PartialEq, Eq)]
 pub(crate) struct ReplEntry {
     pub(crate) query: ReplQuery,
     pub(crate) expected_result: ExpectedResult,
@@ -99,3 +99,142 @@ impl ReplEntry {
 }
 
 pub(crate) const NIX_REPL_LANG_TAG: &str = "nix-repl";
+
+#[cfg(test)]
+mod test {
+    use indoc::indoc;
+    use pretty_assertions::assert_eq;
+
+    use crate::repl::example::ReplExampleEntries;
+
+    use super::{ExpectedResult, ReplEntry, ReplQuery};
+
+    #[derive(PartialEq, Eq, Debug)]
+    struct Case {
+        input: &'static str,
+        expected_output: Vec<ReplEntry>,
+    }
+
+    #[derive(Debug, PartialEq, Eq)]
+    struct Failure {
+        case: Case,
+        actual_output: Vec<ReplEntry>,
+    }
+
+    macro_rules! parse_success {
+        ($(
+            {
+                input: $input:expr,
+                expected_output: [$(
+                    {
+                        query: $query:expr,
+                        expected_result: $expected_result:expr,
+                    },
+                )*],
+            },
+        )*) => {
+            #[test]
+            fn parse_success() {
+                let cases = vec![$(
+                    Case {
+                        input: $input,
+                        expected_output: vec![$(
+                            ReplEntry::new(
+                                ReplQuery::new($query.parse().unwrap()),
+                                ExpectedResult($expected_result.to_owned()),
+                            ),
+                        )*],
+                    },
+                )*];
+
+                test_parse_success_cases(cases);
+            }
+        };
+    }
+
+    fn test_parse_success_cases(cases: Vec<Case>) {
+        let failures: Vec<Failure> = cases
+            .into_iter()
+            .filter_map(|case| {
+                let actual: ReplExampleEntries = case.input.parse().unwrap();
+                let actual_output = actual.0;
+                if actual_output == case.expected_output {
+                    None
+                } else {
+                    Some(Failure {
+                        case,
+                        actual_output,
+                    })
+                }
+            })
+            .collect();
+        assert_eq!(failures, vec![]);
+    }
+
+    parse_success! [
+        {
+            input: indoc! {"
+                nix-repl> 1 + 1
+                2
+
+            "},
+            expected_output: [
+                {
+                    query: "1 + 1\n",
+                    expected_result: "2",
+                },
+            ],
+        },
+        {
+            input: indoc! {"
+                nix-repl> a = 1
+
+            "},
+            expected_output: [
+                {
+                    query: "a = 1\n",
+                    expected_result: "",
+                },
+            ],
+        },
+        {
+            input: indoc! {r#"
+                nix-repl> 1 + 1
+                2
+
+                nix-repl> "a" + "b"
+                "ab"
+
+            "#},
+            expected_output: [
+                {
+                    query: "1 + 1\n",
+                    expected_result: "2",
+                },
+                {
+                    query: "\"a\" + \"b\"\n",
+                    expected_result: "\"ab\"",
+                },
+            ],
+        },
+        {
+            input: indoc! {r#"
+                nix-repl> b = "b"
+
+                nix-repl> 1
+                1
+
+            "#},
+            expected_output: [
+                {
+                    query: "b = \"b\"\n",
+                    expected_result: "",
+                },
+                {
+                    query: "1\n",
+                    expected_result: "1",
+                },
+            ],
+        },
+    ];
+}