[test-improver] Improve tests for proxy/graphql_rewrite

[github-actions]

File Analyzed

• Test File: internal/proxy/graphql_rewrite_test.go
• Package: internal/proxy
• Changes: +24 lines (3 new test cases added to TestFindParentField)

Improvements Made

Increased Coverage

Three previously uncovered branches in findParentField (graphql_rewrite.go) are now tested:

• ✅ depth-- branch (line 206): added "sibling closed block before nodes" — a query like field { sub { x } nodes { y } } where scanning backward crosses a balanced {...} block at the same nesting level before reaching the enclosing { of the parent field.
• ✅ parenDepth++ branch (line 229): added "nested parentheses in field arguments" — a query like field(func(x)) { nodes { y } } where the argument list contains a nested call, causing the inner ) to increment parenDepth before the inner ( decrements it.
• ✅ i+1 >= end guard (lines 245–248): added "no field name before enclosing brace" — a query like { nodes { y } } where the enclosing { is the top-level anonymous selection set with no identifier before it, returning "".

Previous coverage: 81.8%
New coverage: 97.0%
Improvement: +15.2 percentage points

Overall proxy package: 91.1% → 91.7%

Cleaner Test Structure

• New cases follow the existing table-driven pattern with t.Run subtests and inline comments explaining which code path each case exercises.

Test Execution

=== RUN   TestFindParentField
=== RUN   TestFindParentField/simple_connection
=== RUN   TestFindParentField/connection_with_totalCount_before_nodes
=== RUN   TestFindParentField/nested_connection
=== RUN   TestFindParentField/connection_without_args
=== RUN   TestFindParentField/sibling_closed_block_before_nodes
=== RUN   TestFindParentField/nested_parentheses_in_field_arguments
=== RUN   TestFindParentField/no_field_name_before_enclosing_brace
--- PASS: TestFindParentField (0.00s)
ok  	github.com/github/gh-aw-mcpg/internal/proxy	coverage: 91.7% of statements

All existing tests continue to pass.

Why These Changes?

findParentField is responsible for identifying the GraphQL connection field that owns a nodes block — critical for the guard field injection logic. The three added test cases each target a distinct control-flow branch that had no coverage:

1. The depth counter that tracks balanced {...} blocks when scanning backward was only tested in its increment path; the decrement path needed a query with a sibling closed block.
2. The parenDepth counter for skipping argument lists was only tested with simple single-depth args; nested calls required a second test.
3. The defensive return "" when no identifier precedes the enclosing brace had no test at all.

---

Generated by Test Improver Workflow
Focuses on better patterns, increased coverage, and more stable tests

Warning

Firewall blocked 1 domain

The following domain was blocked by the firewall during workflow execution:

• index.crates.io

To allow these domains, add them to the network.allowed list in your workflow frontmatter:

network:
  allowed:
    - defaults
    - "index.crates.io"

See Network Configuration for more information.

Generated by Test Improver · 1.6K AIC · ⊞ 29.5K · ◷

[Copilot]

Pull request overview

Improves unit test coverage for the GraphQL query rewrite helper findParentField in internal/proxy, which is used to safely inject guard fields into nodes { ... } selections.

Changes:

• Added a test case covering backward-scan brace depth decrement (depth--) when encountering a closed sibling selection set before nodes.
• Added a test case intended to cover nested-parentheses handling in argument scanning (parenDepth++).
• Added a test case covering the defensive guard that returns "" when no identifier precedes the enclosing { (top-level anonymous selection set).

Show a summary per file

File	Description
internal/proxy/graphql_rewrite_test.go	Adds 3 table-driven cases to increase coverage of findParentField branch behavior.

Copilot's findings

Tip

Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

• Files reviewed: 1/1 changed files
• Comments generated: 1