feat(vscode-ext): support source opening

[Binlogo]

What does this PR do?

It enables quick opening of the source file in VSCode using CMD+click with the Extension.

Preview

[max-sixty]

thanks for the suggestion!

I don't know this code well, so I asked Claude to take a look. Can we indeed simplify? If not, I trust you more than Claude; but would like to keep this code simple if possible

Details

⏺ Based on my analysis, here's my review of PR #817:

Summary

The PR uses the correct API pattern (DocumentLinkProvider + custom command) since VSCode's DocumentLink doesn't support line/column positions directly. However, the implementation is over-engineered for cases
that don't exist in insta's actual snapshot format.

Issues Found

1. Handles Non-Existent Fields (vscode-insta/src/SnapshotDocumentLinkProvider.ts:84-96)

The parser handles line: and column: fields that don't exist in insta's metadata structure:

const lineMatch = text.match(/^(?:assertion_)?line:\s*(\d+)/); // "line:" doesn't exist
const columnMatch = text.match(/^column:\s*(\d+)/); // "column:" doesn't exist

Reality: Insta only has assertion_line in pending snapshots (see insta/src/snapshot.rs:232-276). No line: or column: fields exist.

2. Quote Handling Complexity (SnapshotDocumentLinkProvider.ts:45-51)

The code handles quoted vs unquoted paths, but insta's YAML output doesn't quote source paths:

const hasQuotes = sourcePath.startsWith(""") && sourcePath.endsWith(""");
if (hasQuotes && sourcePath.length >= 2) {
sourcePath = sourcePath.slice(1, -1);
// ... adjust positions ...
}

Reality: All snapshot examples show unquoted paths: source: insta/tests/test_basic.rs

3. Trailing Location Parsing (SnapshotDocumentLinkProvider.ts:54-66)

Handles source: path/to/file:10:5 format, but insta stores line numbers separately in assertion_line, not in the source path.

4. Over-Complex Path Resolution (SnapshotDocumentLinkProvider.ts:116-139)

Tries multiple fallback paths (workspace folder, all workspace folders, document directory) with file existence checks. For a Rust project, snapshots are always relative to the workspace root.

Simpler Approach

function extractSourceLink(document: TextDocument): SourceLink | undefined {
// Parse YAML frontmatter between --- markers
const text = document.getText();
const frontmatterMatch = text.match(/^---\n([\s\S]*?)\n---/);
if (!frontmatterMatch) return undefined;

const frontmatter = frontmatterMatch[1];

// Extract source (required) and assertion_line (optional, only in .snap.new files)
const sourceMatch = frontmatter.match(/^source:\s*(.+)$/m);
const lineMatch = frontmatter.match(/^assertion_line:\s*(\d+)$/m);

if (!sourceMatch) return undefined;

const sourcePath = sourceMatch[1].trim();
const line = lineMatch ? parseInt(lineMatch[1], 10) : undefined;

// Calculate range for the clickable link
const sourceLineStart = text.indexOf(`source: ${sourcePath}`);
const lineNumber = text.substring(0, sourceLineStart).split('\n').length - 1;
const startChar = text.substring(sourceLineStart).indexOf(sourcePath);

return {
  sourcePath,
  line,
  range: new Range(
    new Position(lineNumber, startChar),
    new Position(lineNumber, startChar + sourcePath.length)
  )
};

}

async function resolveSourceUri(
document: TextDocument,
sourcePath: string
): Promise<Uri | undefined> {
// Handle absolute paths
if (path.isAbsolute(sourcePath)) {
return Uri.file(sourcePath);
}

// Resolve relative to workspace root (snapshots are always workspace-relative)
const workspace = workspace.getWorkspaceFolder(document.uri);
return workspace ? Uri.file(path.join(workspace.uri.fsPath, sourcePath)) : undefined;

}

What's Good

• ✅ Correct use of command pattern (necessary due to VSCode API limitation)
• ✅ Good UX with CMD+click to jump to source
• ✅ Proper handling of both file and inline snapshots

Recommendations

Option 1: Simplify to match actual format

• Remove line:, column: field handling
• Remove quote handling
• Remove trailing location parsing
• Simplify path resolution to workspace-relative only

Option 2: Keep defensive code

• If planning future insta features (like column support), document this
• Add comments explaining why handling non-existent cases

The command pattern itself is standard and correct—the complexity is in the parser, not the VSCode integration pattern.

[Binlogo]

You're right; the current implementation is a bit complicated. This is my first time contributing to a VSCode extension with Codex's help, and I thought quick open would be useful.

I've simplified the code. Please take a look.

[max-sixty]

super, thank you @Binlogo !