chore: import upstream snapshot with attribution

.opencode/tools/git-summary.ts

@@ -0,0 +1,76 @@
+/**
+ * ECC Custom Tool: Git Summary
+ *
+ * Returns branch/status/log/diff details for the active repository.
+ */
+
+import { tool, type ToolDefinition } from "@opencode-ai/plugin/tool"
+import { execFileSync } from "child_process"
+
+// Conservative subset of git's allowed ref-name characters. Rejects shell
+// metacharacters and option-like leading `-` so a model-supplied baseBranch
+// cannot inject into the shell command line built below.
+const SAFE_GIT_REF = /^[A-Za-z0-9._/-]+$/
+
+function isSafeRef(ref: string): boolean {
+  if (typeof ref !== "string" || ref.length === 0 || ref.length > 200) return false
+  if (!SAFE_GIT_REF.test(ref)) return false
+  if (ref.startsWith("-") || ref.startsWith(".") || ref.startsWith("/")) return false
+  if (ref.includes("..") || ref.includes("//")) return false
+  return true
+}
+
+function isSafeDepth(value: unknown): value is number {
+  return typeof value === "number" && Number.isInteger(value) && value > 0 && value <= 1000
+}
+
+const gitSummaryTool: ToolDefinition = tool({
+  description:
+    "Generate git summary with branch, status, recent commits, and optional diff stats.",
+  args: {
+    depth: tool.schema
+      .number()
+      .optional()
+      .describe("Number of recent commits to include (default: 5)"),
+    includeDiff: tool.schema
+      .boolean()
+      .optional()
+      .describe("Include diff stats against base branch (default: true)"),
+    baseBranch: tool.schema
+      .string()
+      .optional()
+      .describe("Base branch for diff comparison (default: main)"),
+  },
+  async execute(args, context) {
+    const cwd = context.worktree || context.directory
+    const depth = isSafeDepth(args.depth) ? args.depth : 5
+    const includeDiff = args.includeDiff ?? true
+    const baseBranch = args.baseBranch ?? "main"
+
+    const result: Record<string, string> = {
+      branch: runArgs(["branch", "--show-current"], cwd) || "unknown",
+      status: runArgs(["status", "--short"], cwd) || "clean",
+      log: runArgs(["log", "--oneline", `-${depth}`], cwd) || "no commits found",
+    }
+
+    if (includeDiff) {
+      result.stagedDiff = runArgs(["diff", "--cached", "--stat"], cwd) || ""
+      result.branchDiff = isSafeRef(baseBranch)
+        ? runArgs(["diff", `${baseBranch}...HEAD`, "--stat"], cwd) ||
+          `unable to diff against ${baseBranch}`
+        : `unable to diff against ${baseBranch} (invalid ref)`
+    }
+
+    return JSON.stringify(result)
+  },
+})
+
+export default gitSummaryTool
+
+function runArgs(args: string[], cwd: string): string {
+  try {
+    return execFileSync("git", args, { cwd, encoding: "utf-8", stdio: ["ignore", "pipe", "pipe"] }).trim()
+  } catch {
+    return ""
+  }
+}