feat: use dynamic fetch depth based on PR commit count

- Replace fixed depth of 20 with dynamic calculation
- Use Math.max(commitCount, 20) to ensure minimum context

README.md

@@ -347,15 +347,8 @@ Claude does **not** have access to execute arbitrary Bash commands by default. I
 ```yaml
 - uses: anthropics/claude-code-action@beta
   with:
-    allowed_tools: |
+    allowed_tools: "Bash(npm install),Bash(npm run test),Edit,Replace,NotebookEditCell"
-      Bash(npm install)
+    disallowed_tools: "TaskOutput,KillTask"
-      Bash(npm run test)
-      Edit
-      Replace
-      NotebookEditCell
-    disallowed_tools: |
-      TaskOutput
-      KillTask
     # ... other inputs
 ```
 

src/github/context.ts

@@ -52,8 +52,14 @@ export function parseGitHubContext(): ParsedGitHubContext {
     inputs: {
       triggerPhrase: process.env.TRIGGER_PHRASE ?? "@claude",
       assigneeTrigger: process.env.ASSIGNEE_TRIGGER ?? "",
-      allowedTools: parseMultilineInput(process.env.ALLOWED_TOOLS ?? ""),
+      allowedTools: (process.env.ALLOWED_TOOLS ?? "")
-      disallowedTools: parseMultilineInput(process.env.DISALLOWED_TOOLS ?? ""),
+        .split(",")
+        .map((tool) => tool.trim())
+        .filter((tool) => tool.length > 0),
+      disallowedTools: (process.env.DISALLOWED_TOOLS ?? "")
+        .split(",")
+        .map((tool) => tool.trim())
+        .filter((tool) => tool.length > 0),
       customInstructions: process.env.CUSTOM_INSTRUCTIONS ?? "",
       directPrompt: process.env.DIRECT_PROMPT ?? "",
       baseBranch: process.env.BASE_BRANCH,
@@ -110,14 +116,6 @@ export function parseGitHubContext(): ParsedGitHubContext {
   }
 }
 
-export function parseMultilineInput(s: string): string[] {
-  return s
-    .split(/,|[\n\r]+/)
-    .map((tool) => tool.replace(/#.+$/, ""))
-    .map((tool) => tool.trim())
-    .filter((tool) => tool.length > 0);
-}
-
 export function isIssuesEvent(
   context: ParsedGitHubContext,
 ): context is ParsedGitHubContext & { payload: IssuesEvent } {

src/github/operations/branch.ts

@@ -45,9 +45,16 @@ export async function setupBranch(
 
       const branchName = prData.headRefName;
 
-      // Execute git commands to checkout PR branch (shallow fetch for performance)
+      // Determine optimal fetch depth based on PR commit count, with a minimum of 20
-      // Fetch the branch with a depth of 20 to avoid fetching too much history, while still allowing for some context
+      const commitCount = prData.commits.totalCount;
-      await $`git fetch origin --depth=20 ${branchName}`;
+      const fetchDepth = Math.max(commitCount, 20);
+
+      console.log(
+        `PR #${entityNumber}: ${commitCount} commits, using fetch depth ${fetchDepth}`,
+      );
+
+      // Execute git commands to checkout PR branch (dynamic depth based on PR size)
+      await $`git fetch origin --depth=${fetchDepth} ${branchName}`;
       await $`git checkout ${branchName}`;
 
       console.log(`Successfully checked out PR branch for PR #${entityNumber}`);

test/github/context.test.ts

@@ -1,57 +0,0 @@
-import { describe, it, expect } from "bun:test";
-import { parseMultilineInput } from "../../src/github/context";
-
-describe("parseMultilineInput", () => {
-  it("should parse a comma-separated string", () => {
-    const input = `Bash(bun install),Bash(bun test:*),Bash(bun typecheck)`;
-    const result = parseMultilineInput(input);
-    expect(result).toEqual([
-      "Bash(bun install)",
-      "Bash(bun test:*)",
-      "Bash(bun typecheck)",
-    ]);
-  });
-
-  it("should parse multiline string", () => {
-    const input = `Bash(bun install)
-Bash(bun test:*)
-Bash(bun typecheck)`;
-    const result = parseMultilineInput(input);
-    expect(result).toEqual([
-      "Bash(bun install)",
-      "Bash(bun test:*)",
-      "Bash(bun typecheck)",
-    ]);
-  });
-
-  it("should parse comma-separated multiline line", () => {
-    const input = `Bash(bun install),Bash(bun test:*)
-Bash(bun typecheck)`;
-    const result = parseMultilineInput(input);
-    expect(result).toEqual([
-      "Bash(bun install)",
-      "Bash(bun test:*)",
-      "Bash(bun typecheck)",
-    ]);
-  });
-
-  it("should ignore comments", () => {
-    const input = `Bash(bun install),
-Bash(bun test:*) # For testing
-# For type checking
-Bash(bun typecheck)
-`;
-    const result = parseMultilineInput(input);
-    expect(result).toEqual([
-      "Bash(bun install)",
-      "Bash(bun test:*)",
-      "Bash(bun typecheck)",
-    ]);
-  });
-
-  it("should parse an empty string", () => {
-    const input = "";
-    const result = parseMultilineInput(input);
-    expect(result).toEqual([]);
-  });
-});