From b15297e7d9a21e3ce05c31a38da20008c1bbe9b4 Mon Sep 17 00:00:00 2001
From: Christopher Chang <51393127+chriscerie@users.noreply.github.com>
Date: Tue, 15 Aug 2023 07:46:39 -0700
Subject: [PATCH] Show missing required param message when given in standard
 library format

---
 CHANGELOG.md                                       |  1 +
 selene-lib/src/lints/standard_library.rs           | 14 +++++++++++++-
 selene-lib/tests/lints/standard_library/assert.lua |  1 +
 .../tests/lints/standard_library/assert.stderr     |  8 ++++++++
 4 files changed, 23 insertions(+), 1 deletion(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 53f47f66..b120375f 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -11,6 +11,7 @@ This project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.htm
 - `roblox_incorrect_roact_usage` now lints for illegal `Name` property
 - Added `ignore_pattern` config to `global_usage`, which will ignore any global variables with names that match the pattern
 - `roblox_incorrect_roact_usage` now checks for incorrect Roact17's `createElement` usage on variables named `React`. For Roact17 only, `key`, `children`, and `ref` are valid properties to Roblox instances.
+- When given in standard library format, additional information now shows up in `incorrect_standard_library_use` missing required parameter errors.
 
 ### Fixed
 - `string.pack` and `string.unpack` now have proper function signatures in the Lua 5.3 standard library.
diff --git a/selene-lib/src/lints/standard_library.rs b/selene-lib/src/lints/standard_library.rs
index 8872238a..f5e0aa99 100644
--- a/selene-lib/src/lints/standard_library.rs
+++ b/selene-lib/src/lints/standard_library.rs
@@ -568,7 +568,17 @@ impl Visitor for StandardLibraryVisitor<'_> {
         if (arguments_length < expected_args && !maybe_more_arguments)
             || (!vararg && arguments_length > max_args)
         {
-            self.diagnostics.push(Diagnostic::new(
+            let required_param_message = function
+                .arguments
+                .get(arguments_length)
+                .into_iter()
+                .filter_map(|arg| match &arg.required {
+                    Required::Required(Some(message)) => Some(message.clone()),
+                    _ => None,
+                })
+                .collect();
+
+            self.diagnostics.push(Diagnostic::new_complete(
                 "incorrect_standard_library_use",
                 format!(
                     "standard library function `{}` requires {} parameters, {} passed",
@@ -577,6 +587,8 @@ impl Visitor for StandardLibraryVisitor<'_> {
                     argument_types.len(),
                 ),
                 Label::from_node(call, None),
+                required_param_message,
+                Vec::new(),
             ));
         }
 
diff --git a/selene-lib/tests/lints/standard_library/assert.lua b/selene-lib/tests/lints/standard_library/assert.lua
index 06473166..e6442caf 100644
--- a/selene-lib/tests/lints/standard_library/assert.lua
+++ b/selene-lib/tests/lints/standard_library/assert.lua
@@ -6,3 +6,4 @@ assert(...)
 assert(true)
 assert(true, "message", call())
 assert(true, "message", ...)
+assert()
diff --git a/selene-lib/tests/lints/standard_library/assert.stderr b/selene-lib/tests/lints/standard_library/assert.stderr
index 25fc666c..1974ef1f 100644
--- a/selene-lib/tests/lints/standard_library/assert.stderr
+++ b/selene-lib/tests/lints/standard_library/assert.stderr
@@ -3,6 +3,8 @@ error[incorrect_standard_library_use]: standard library function `assert` requir
   │
 6 │ assert(true)
   │ ^^^^^^^^^^^^
+  │
+  = A failed assertion without a message is unhelpful to users.
 
 error[incorrect_standard_library_use]: standard library function `assert` requires 2 parameters, 3 passed
   ┌─ assert.lua:7:1
@@ -16,3 +18,9 @@ error[incorrect_standard_library_use]: standard library function `assert` requir
 8 │ assert(true, "message", ...)
   │ ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
+error[incorrect_standard_library_use]: standard library function `assert` requires 2 parameters, 0 passed
+  ┌─ assert.lua:9:1
+  │
+9 │ assert()
+  │ ^^^^^^^^
+