Lopper for VS Code

Lopper brings dependency-surface analysis into VS Code with inline diagnostics and hover context across supported adapters, including Kotlin Android and PowerShell, plus safe JS/TS quick fixes powered by the lopper CLI.

What it does

• Flags unused dependency imports directly in editors covered by supported Lopper adapters.
• Shows dependency usage, license, provenance, risk cues, and recommendation context in hovers.
• Offers deterministic quick fixes for safe --suggest-only JS/TS subpath rewrites.
• Supports package, repo, and changed-packages analysis scope modes directly in VS Code.
• Keeps a status-bar summary and manual refresh commands, including a force-fresh option.

Adapter mode

The extension uses the same adapter IDs as the lopper CLI.

• lopper.language = auto is the default. It prefers the active or saved editor's adapter when it can infer one, including Android Gradle Kotlin/Java modules, then falls back to lopper CLI auto detection.
• lopper.language = all runs every matching adapter in the workspace and merges the results.
• You can pin any supported adapter directly: cpp, dart, dotnet, elixir, go, js-ts, jvm, kotlin-android, php, powershell, python, ruby, rust, or swift.

Binary setup

The extension shells out to lopper.

• If lopper is already on your PATH, the extension will use it automatically.
• If your repo contains bin/lopper, the extension will use that first after you trust the workspace.
• If no local binary is available, the extension can download a matching GitHub release into extension-managed storage.
• You can always override detection with lopper.binaryPath or LOPPER_BINARY_PATH.
• Workspace-local binaries, including bin/lopper and lopper.binaryPath values inside the repo, are blocked until the workspace is trusted.

Install

From the VS Code Marketplace after publish:

code --install-extension BenRanford.vscode-lopper

From a GitHub release VSIX:

code --install-extension lopper-vscode-<version>.vsix

Settings

• lopper.language: adapter mode, defaulting to auto
• lopper.scopeMode: analysis scope mode (package, repo, changed-packages)
• lopper.binaryPath: explicit path to the lopper binary
• lopper.topN: max dependencies to analyse on each refresh
• lopper.autoRefresh: refresh on saves that match the selected adapter mode
• lopper.autoDownloadBinary: enable or disable managed binary downloads
• lopper.managedBinaryTag: optional release tag override for managed installs

Commands

• Lopper: Refresh Diagnostics: refresh using the configured scope and session cache.
• Lopper: Refresh Diagnostics (Force Fresh): bypass cache and re-run analysis.
• Lopper: Refresh Diagnostics (Scope: package|repo|changed-packages): run using an explicit scope mode.

The extension deduplicates in-flight refreshes per folder/language/scope, prevents stale runs from overwriting newer diagnostics, and logs refresh lifecycle states to the Lopper output channel.

Development

make build
make vscode-extension-install
make vscode-extension-test
make vscode-extension-package

Repository docs: https://github.com/ben-ranford/lopper#readme