feat: custom branch name templates (#571)

* Add branch-name-template config option * Logging * Use branch name template * Add label to template variables * Add description template variable * More concise description for branch_name_template * Remove more granular time template variables * Only fetch first label * Add check for empty template-generated name * Clean up comments, docstrings * Merge createBranchTemplateVariables into generateBranchName * Still replace undefined values * Fall back to default on duplicate branch * Parameterize description wordcount * Remove some over-explanatory comments * NUM_DESCRIPTION_WORDS: 3 -> 5
2026-01-27 01:52:24 +08:00 · 2026-01-07 20:17:26 -05:00
parent cefa60067a
commit c247cb152d
9 changed files with 415 additions and 14 deletions
--- a/src/utils/branch-template.ts
+++ b/src/utils/branch-template.ts
@@ -0,0 +1,96 @@
+#!/usr/bin/env bun
+
+/**
+ * Branch name template parsing and variable substitution utilities
+ */
+
+const NUM_DESCRIPTION_WORDS = 5;
+
+/**
+ * Extracts the first `numWords` words from a title and converts them to kebab-case
+ */
+function extractDescription(title: string, numWords: number = NUM_DESCRIPTION_WORDS): string {
+  if (!title || title.trim() === "") {
+    return "";
+  }
+
+  return title
+    .trim()
+    .split(/\s+/)
+    .slice(0, numWords) // Only first `numWords` words
+    .join("-")
+    .toLowerCase()
+    .replace(/[^a-z0-9-]/g, "") // Remove non-alphanumeric except hyphens
+    .replace(/-+/g, "-") // Replace multiple hyphens with single
+    .replace(/^-|-$/g, ""); // Remove leading/trailing hyphens
+}
+
+export interface BranchTemplateVariables {
+  prefix: string;
+  entityType: string;
+  entityNumber: number;
+  timestamp: string;
+  sha?: string;
+  label?: string;
+  description?: string;
+}
+
+/**
+ * Replaces template variables in a branch name template
+ * Template format: {{variableName}}
+ */
+export function applyBranchTemplate(
+  template: string,
+  variables: BranchTemplateVariables,
+): string {
+  let result = template;
+
+  // Replace each variable
+  Object.entries(variables).forEach(([key, value]) => {
+    const placeholder = `{{${key}}}`;
+    const replacement = value ? String(value) : "";
+    result = result.replaceAll(placeholder, replacement);
+  });
+
+  return result;
+}
+
+/**
+ * Generates a branch name from the provided `template` and set of `variables`. Uses a default format if the template is empty or produces an empty result.
+ */
+export function generateBranchName(
+  template: string | undefined,
+  branchPrefix: string,
+  entityType: string,
+  entityNumber: number,
+  sha?: string,
+  label?: string,
+  title?: string,
+): string {
+  const now = new Date();
+
+  const variables: BranchTemplateVariables = {
+    prefix: branchPrefix,
+    entityType,
+    entityNumber,
+    timestamp: `${now.getFullYear()}${String(now.getMonth() + 1).padStart(2, "0")}${String(now.getDate()).padStart(2, "0")}-${String(now.getHours()).padStart(2, "0")}${String(now.getMinutes()).padStart(2, "0")}`,
+    sha: sha?.substring(0, 8), // First 8 characters of SHA
+    label: label || entityType, // Fall back to entityType if no label
+    description: title ? extractDescription(title) : undefined,
+  };
+
+  if (template?.trim()) {
+    const branchName = applyBranchTemplate(template, variables);
+
+    // Some templates could produce empty results- validate
+    if (branchName.trim().length > 0) return branchName;
+
+    console.log(
+      `Branch template '${template}' generated empty result, falling back to default format`,
+    );
+  }
+
+  const branchName = `${branchPrefix}${entityType}-${entityNumber}-${variables.timestamp}`;
+  // Kubernetes compatible: lowercase, max 50 chars, alphanumeric and hyphens only
+  return branchName.toLowerCase().substring(0, 50);
+}