Add comprehensive test coverage and refactor extension #43

johnbillion · 2025-10-01T14:47:03Z

Summary

✅ Added comprehensive test infrastructure using @vscode/test-cli and mocha
✅ Created 17 tests covering all major functionality
✅ Refactored monolithic 618-line extension.ts into clean modular structure (now 14 lines!)
✅ Updated CI/CD workflow to run tests
✅ Updated documentation with test instructions

Test Coverage

The test suite includes:

Hook completion (actions and filters)
Callback completion (closures, arrow functions, utility functions)
Hover provider with documentation links
Edge cases (all hook functions, quotes, whitespace handling)

Breaking Changes

None - this is purely internal refactoring with comprehensive test coverage to ensure functionality remains unchanged.

…tructure.

…nctions

…ator

- Refactor codebase to separate pure logic from VS Code adapters - Create src/core/ directory with framework-agnostic code - Add Stryker mutation testing configuration - Add 51 unit tests for core modules - Achieve 63.70% mutation score (up from 5.48%) Test improvements: - typeHelpers: 0% → 62.50% (45 mutants killed) - snippetGenerator: 0% → 73.33% (55 mutants killed) - docblockGenerator: 0% → 62.79% (27 mutants killed) - hookHelpers: 0% → 56.58% (43 mutants killed) - matchers: 61.54% maintained (16 mutants killed) All 208 existing tests pass with zero regressions. 🤖 Generated with Claude Code (https://claude.com/claude-code) Co-Authored-By: Claude <noreply@anthropic.com>

Copilot

Pull request overview

This PR implements a comprehensive refactoring that transforms a monolithic 618-line extension.ts file into a clean, modular architecture with extensive test coverage. The refactoring maintains backward compatibility through re-export wrapper modules while establishing a robust test infrastructure using @vscode/test-cli, mocha, and mutation testing with Stryker.

Key Changes:

Refactored extension.ts from 618 lines to 14 lines by extracting functionality into dedicated modules
Added comprehensive test suite with 17 tests covering hook completion, callback completion, hover providers, and edge cases
Implemented mutation testing infrastructure with 50% mutation score threshold
Updated CI/CD workflow to run tests automatically

Reviewed changes

Copilot reviewed 39 out of 41 changed files in this pull request and generated 10 comments.

Show a summary per file

File	Description
src/extension.ts	Simplified to 14 lines - now only imports and registers providers
src/providers/*.ts	New provider modules for hook completion, callback completion, and hover functionality
src/core/*.ts	Core business logic extracted into dedicated modules (typeHelpers, snippetGenerator, matchers, hookHelpers, docblockGenerator)
src/utils/*.ts	Backward compatibility wrappers that re-export from core modules
src/types/index.ts	Centralized type definitions
src/test/suite/*.test.ts	Integration tests running in headless VS Code instance
src/test/unit/*.test.ts	Unit tests for core modules
stryker.config.json	Mutation testing configuration with 50% break threshold
.vscode-test.mjs	VS Code test runner configuration
.mocharc.unit.json	Mocha configuration for unit tests
package.json	Added test scripts and dev dependencies for testing infrastructure
CONTRIBUTING.md	Updated with new code structure documentation and test instructions
.github/workflows/test.yml	Added test execution and mutation testing steps to CI/CD
.vscodeignore	Added exclusions for test output directories
.eslintrc.json	Added test-specific linting rules

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Copilot · 2026-01-03T00:13:06Z

src/providers/callbackCompletionProvider.ts

+	params: Array<{ types?: string[] }>,
+): vscode.CompletionItem[] {
+	const completions: vscode.CompletionItem[] = [];
+


The utility function completions assume params[0] exists without checking if the params array is empty. While filters typically have at least one parameter, this could cause a runtime error if a filter hook is defined without parameters. Consider adding a guard check: if (params.length === 0) return []; at the start of this function.

Suggested change

if (params.length === 0) {

return [];

}

Copilot · 2026-01-03T00:13:07Z

src/providers/hookCompletionProvider.ts

+		{
+			provideCompletionItems(document: vscode.TextDocument, position: vscode.Position) {
+				// get all text until the `position` and check if it reads a certain value and if so then complete
+				const linePrefix = document.lineAt(position).text.substr(0, position.character);


The .substr() method is deprecated in favor of .substring() or .slice(). Consider updating to use the modern API.

Suggested change

const linePrefix = document.lineAt(position).text.substr(0, position.character);

const linePrefix = document.lineAt(position).text.slice(0, position.character);

Copilot · 2026-01-03T00:13:07Z

src/providers/callbackCompletionProvider.ts

+		'php',
+		{
+			provideCompletionItems(document: vscode.TextDocument, position: vscode.Position) {
+				const linePrefix = document.lineAt(position).text.substr(0, position.character);


The .substr() method is deprecated in favor of .substring() or .slice(). Consider updating to use the modern API.

Suggested change

const linePrefix = document.lineAt(position).text.substr(0, position.character);

const linePrefix = document.lineAt(position).text.substring(0, position.character);

Copilot · 2026-01-03T00:13:07Z

.github/workflows/test.yml

+    - name: Run tests
+      run: xvfb-run -a npm test
+
+    - name: Run mutation testing


The mutation testing step in CI/CD may fail on the first run since it requires a mutation score of at least 50% (based on the 'break' threshold). Consider either making this step non-blocking initially (using 'continue-on-error: true') or adjusting the thresholds until the test suite is more mature.

Suggested change

- name: Run mutation testing

- name: Run mutation testing

continue-on-error: true

Copilot · 2026-01-03T00:13:08Z

.vscodeignore

+out/test/**
 test/**
+.vscode-test.mjs
 tsconfig.json


The .mocharc.unit.json file is missing from the .vscodeignore file. Since this is a test configuration file that's only needed during development, it should be excluded from the published extension to reduce package size.

Suggested change

tsconfig.json

tsconfig.json

.mocharc.unit.json

Copilot · 2026-01-03T00:13:08Z

src/providers/callbackCompletionProvider.ts

+	docBlocksEnabled: boolean,
+): vscode.CompletionItem {
+	const completionItemForArrow = new vscode.CompletionItem('Arrow function', vscode.CompletionItemKind.Function);
+


The arrow function completion assumes params[0] exists without checking if the params array is empty. While filters typically have at least one parameter, this could cause a runtime error if a filter hook is defined without parameters. Consider adding a guard check: if (params.length === 0) return; or if (!params[0]?.variable) return; at the start of this function.

Suggested change

if (!params.length || !params[0]?.variable) {

return completionItemForArrow;

}

Copilot · 2026-01-03T00:13:08Z

src/core/snippetGenerator.ts

+		const returnType = getReturnType(params[0]);
+
+		if (returnType) {
+			if (returnType.nullable) {
+				returnTypeString = ` : ?${returnType.type}`;
+			} else {
+				returnTypeString = ` : ${returnType.type}`;
+			}
+		}
+
+		snippetCallback = `( ${snippetArgsString} )${returnTypeString} {\n\t\${1}\n\treturn \\${params[0].variable};\n}`;
+		documentationCallback = `( ${docArgsString} )${returnTypeString} {\n\treturn ${params[0].variable};\n}`;


The snippet generator assumes params[0] exists when generating filter callbacks without checking if the params array is empty. Lines 38 and 48 access params[0] directly. While filters typically have at least one parameter, this could cause a runtime error if a filter hook is defined without parameters. Consider adding a guard check at the start of the filter block: if (params.length === 0) { /* handle edge case */ }.

Suggested change

const returnType = getReturnType(params[0]);

if (returnType) {

if (returnType.nullable) {

returnTypeString = ` : ?${returnType.type}`;

} else {

returnTypeString = ` : ${returnType.type}`;

}

}

snippetCallback = `( ${snippetArgsString} )${returnTypeString} {\n\t\${1}\n\treturn \\${params[0].variable};\n}`;

documentationCallback = `( ${docArgsString} )${returnTypeString} {\n\treturn ${params[0].variable};\n}`;

if (params.length === 0) {

snippetCallback = `() {\n\t\${1}\n}`;

documentationCallback = `() {\n}`;

} else {

const returnType = getReturnType(params[0]);

if (returnType) {

if (returnType.nullable) {

returnTypeString = ` : ?${returnType.type}`;

} else {

returnTypeString = ` : ${returnType.type}`;

}

}

snippetCallback = `( ${snippetArgsString} )${returnTypeString} {\n\t\${1}\n\treturn \\${params[0].variable};\n}`;

documentationCallback = `( ${docArgsString} )${returnTypeString} {\n\treturn ${params[0].variable};\n}`;

}

Copilot · 2026-01-03T00:13:08Z

src/providers/hoverProvider.ts

+		'php',
+		{
+			provideHover(document, position) {
+				const linePrefix = document.lineAt(position).text.substr(0, position.character);


The .substr() method is deprecated in favor of .substring() or .slice(). Consider updating to use the modern API.

Suggested change

const linePrefix = document.lineAt(position).text.substr(0, position.character);

const linePrefix = document.lineAt(position).text.substring(0, position.character);

Copilot · 2026-01-03T00:13:09Z

src/test/suite/hookCompletion.test.ts

+import * as vscode from 'vscode';
+
+suite('Hook Completion Test Suite', () => {
+	vscode.window.showInformationMessage('Start hook completion tests.');


The showInformationMessage call is executed at suite definition time, not during test execution. This will show the message every time the test file is loaded, which may not be the intended behavior. Consider moving this to a suiteSetup hook or removing it if it's not needed for debugging.

Suggested change

vscode.window.showInformationMessage('Start hook completion tests.');

suiteSetup(() => {

vscode.window.showInformationMessage('Start hook completion tests.');

});

Copilot · 2026-01-03T00:13:09Z

.vscodeignore

+out/test/**
 test/**
+.vscode-test.mjs
 tsconfig.json


The stryker.config.json file is missing from the .vscodeignore file. Since this is a mutation testing configuration file that's only needed during development, it should be excluded from the published extension to reduce package size.

Suggested change

tsconfig.json

tsconfig.json

stryker.config.json

johnbillion and others added 6 commits October 1, 2025 15:45

Add comprehensive test coverage and refactor extension into modular s…

ba76e74

…tructure.

Fix linting errors - add eslint overrides for test files

8b3bf6a

Refactor tests to use matrix-based approach for all WordPress hook fu…

7d60642

…nctions

Add comprehensive unit tests for utils and generators (208 total tests)

c5b42ab

Improve test coverage - add alignment verification for docblock gener…

668b02a

…ator

johnbillion requested a review from Copilot January 3, 2026 00:09

Copilot started reviewing on behalf of johnbillion January 3, 2026 00:09 View session

Copilot AI reviewed Jan 3, 2026

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+	if (params.length === 0) {
+		return [];
+	}

	const linePrefix = document.lineAt(position).text.substr(0, position.character);
	const linePrefix = document.lineAt(position).text.slice(0, position.character);

	- name: Run mutation testing
	- name: Run mutation testing
	continue-on-error: true

+	if (!params.length || !params[0]?.variable) {
+		return completionItemForArrow;
+	}

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johnbillion commented Oct 1, 2025

Summary

Test Coverage

Breaking Changes

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