From 43bf1a8907fc0e48e8ca7b52485a349772e91de9 Mon Sep 17 00:00:00 2001
From: Dhruv Manilawala <dhruvmanila@gmail.com>
Date: Thu, 5 Dec 2024 17:32:48 +0530
Subject: [PATCH] Add tests for "keyword as identifier" syntax errors (#14754)

## Summary

This is related to #13778, more specifically
https://github.com/astral-sh/ruff/issues/13778#issuecomment-2513556004.

This PR adds various test cases where a keyword is being where an
identifier is expected. The tests are to make sure that red knot doesn't
panic, raises the syntax error and the identifier is added to the symbol
table. The final part allows editor related features like renaming the
symbol.
---
 .../resources/mdtest/invalid_syntax.md        | 69 +++++++++++++++++++
 1 file changed, 69 insertions(+)
 create mode 100644 crates/red_knot_python_semantic/resources/mdtest/invalid_syntax.md

diff --git a/crates/red_knot_python_semantic/resources/mdtest/invalid_syntax.md b/crates/red_knot_python_semantic/resources/mdtest/invalid_syntax.md
new file mode 100644
index 0000000000000..2363257e7eb87
--- /dev/null
+++ b/crates/red_knot_python_semantic/resources/mdtest/invalid_syntax.md
@@ -0,0 +1,69 @@
+# Syntax errors
+
+Test cases to ensure that red knot does not panic if there are syntax errors in the source code.
+
+## Keyword as identifiers
+
+When keywords are used as identifiers, the parser recovers from this syntax error by emitting an
+error and including the text value of the keyword to create the `Identifier` node.
+
+### Name expression
+
+```py
+# error: [invalid-syntax]
+pass = 1
+
+# error: [invalid-syntax]
+# error: [invalid-syntax]
+type pass = 1
+
+# error: [invalid-syntax]
+# error: [invalid-syntax]
+# error: [invalid-syntax]
+# error: [invalid-syntax]
+# error: [invalid-syntax]
+def True(for):
+    # error: [invalid-syntax]
+    pass
+
+# TODO: Why is there two diagnostics for the same error?
+
+# error: [invalid-syntax]
+# error: [invalid-syntax]
+# error: [invalid-syntax]
+# error: [unresolved-reference] "Name `pass` used when not defined"
+# error: [unresolved-reference] "Name `pass` used when not defined"
+for while in pass:
+    pass
+
+# error: [invalid-syntax]
+# error: [unresolved-reference] "Name `in` used when not defined"
+while in:
+    pass
+
+# error: [invalid-syntax]
+# error: [invalid-syntax]
+# error: [unresolved-reference] "Name `match` used when not defined"
+match while:
+    # error: [invalid-syntax]
+    # error: [invalid-syntax]
+    # error: [invalid-syntax]
+    # error: [unresolved-reference] "Name `case` used when not defined"
+    case in:
+        # error: [invalid-syntax]
+        # error: [invalid-syntax]
+        pass
+```
+
+### Attribute expression
+
+```py
+# TODO: Why is there two diagnostics for the same error?
+# TODO: Check when support for attribute expressions is added
+
+# error: [invalid-syntax]
+# error: [unresolved-reference] "Name `foo` used when not defined"
+# error: [unresolved-reference] "Name `foo` used when not defined"
+for x in foo.pass:
+    pass
+```