Why Does This Exist

Why Does This Exist helps reviewers understand code context by showing the last commit that changed a line, along with optional Jira ticket enrichment when a ticket id is present.

Features

• Hover over a line to see the last commit that touched it
• View author, date, and commit message context
• Optionally enrich ticket ids with Jira metadata
• Works entirely from the local git history and VS Code

Installation

Install from the VS Code Marketplace or build a local package with:

npm install
npm run compile
npx @vscode/vsce package

Development

See CONTRIBUTING.md for local development and pull request guidance.

Parts

• src/blame.ts — pure porcelain-parsing/formatting functions (no vscode dependency), unit-tested without a repo or a VS Code host: npm run compile && npm test.
• src/jira.ts — optional Jira enrichment (fail-soft: any failure falls back to a plain ticket link).
• src/extension.ts — the hover provider, blame caching, and the Jira-token commands. Requires Node.js + npm to build (npm install && npm run compile).

Installing the .vsix manually (sharing with your team)

why-does-this-exist-hover-0.1.0.vsix is a single file — copy it anywhere (network share, Slack/Teams, email) and any teammate can install it without needing Node.js or building anything themselves. There is no companion tool to bundle; the only requirement on the receiving machine is git on PATH.

Option A — VS Code UI:

1. Open the Extensions view (Ctrl+Shift+X).
2. Click the ... (More Actions) menu at the top of the panel.
3. Choose Install from VSIX...
4. Browse to the .vsix file and select it.
5. Reload VS Code if prompted.

Option B — command line:

code --install-extension why-does-this-exist-hover-0.1.0.vsix

To update to a newer version later, just repeat either step with the new .vsix. To remove it: Extensions view ... menu, or code --uninstall-extension local.why-does-this-exist-hover.

How it triggers

Automatic — hover any line in a file that's tracked by git and inside a workspace folder. No command needed for the git-only hover. A file not under git, or a line with no committed blame (new/unsaved), simply shows no hover. If the document has unsaved edits, the hover adds a note that blame may not match the current line (blame is always computed against the file on disk).

Jira enrichment is off until you turn it on:

1. Set whyHover.jiraBaseUrl to your instance (e.g. https://yourteam.atlassian.net).
2. Run "Why Hover: Set Jira Token..." — prompts for an email + API token (Jira Cloud, the default basic auth scheme) or just a token (whyHover.jiraAuthScheme: "bearer" for Jira Server/Data Center's Personal Access Tokens). Stored only in VS Code's SecretStorage — never in settings, never logged.
3. Hover a line whose commit message contains a ticket id (default pattern matches PROJ-123-style ids) — the hover now shows the issue's summary and status alongside the link.

Any Jira failure (no token, wrong scheme, network error, wrong ticket) silently falls back to a plain link to the ticket — never an error, never a blocked hover, bounded by whyHover.jiraTimeoutMs (default 3000ms). Run "Why Hover: Clear Jira Token" to remove stored credentials.

Settings

• whyHover.ticketPattern (default [A-Z][A-Z0-9]+-\d+)
• whyHover.jiraBaseUrl (default empty — enrichment off)
• whyHover.jiraAuthScheme ("basic" | "bearer", default "basic")
• whyHover.jiraTimeoutMs (default 3000)

Security

Commit messages and Jira issue text are rendered as Markdown with isTrusted = false and manually escaped — a crafted commit message or issue title cannot inject a clickable command: link into the hover.

Status

Unit tests for the porcelain blame parser, commit-message splitting, and ticket extraction (including an all-zero/uncommitted hash and an invalid user-supplied regex pattern) all pass with no repo or network required. Extension built, packaged, and installed into VS Code. The working directory this was built in is not a git repository, so the live hover-in-a-real-repo path and the Jira enrichment path (which needs a reachable Atlassian instance and a valid token) have not been manually exercised — both need to be verified by hand in an actual git repository.