Add base-branch field for cross-repo PRs targeting non-default branches

[Copilot]

Implementation Complete ✅

Successfully merged main branch and recompiled all workflows with both base-branch and footer fields working together.

Changes Made

Merge Conflicts Resolved:

• ✅ Combined BaseBranch and Footer fields in CreatePullRequestsConfig struct
• ✅ Updated handler config builder to support both fields
• ✅ Updated JSON schema to include both properties
• ✅ Updated documentation with both fields

Validation:

• ✅ All unit tests pass (including new footer tests from main)
• ✅ All integration tests pass
• ✅ Manual compilation confirms both fields work together
• ✅ All 148 workflows recompiled successfully

Usage Example

Both fields can now be used together:

safe-outputs:
  create-pull-request:
    target-repo: "microsoft/vscode-docs"
    base-branch: vnext    # NEW: Custom base branch
    footer: false         # NEW from main: Control footer visibility
    draft: true

Compiles to:

{
  "create_pull_request": {
    "base_branch": "vnext",
    "footer": false,
    "target-repo": "microsoft/vscode-docs",
    "draft": true
  }
}

Backward Compatibility

Both fields maintain backward compatibility:

• base-branch defaults to ${{ github.ref_name }} when not specified
• footer defaults to true when not specified

Original prompt

---

This section details on the original issue you should resolve

<issue_title>create-pull-request safe output: add base-branch field for cross-repo PRs targeting non-default branches</issue_title>
<issue_description>(note, AI generated and working with @benvillalobos on similar cross repo engineering flows)

Summary

The create-pull-request safe output hard-codes the base branch to ${{ github.ref_name }}, which is the branch of the workflow repository that the dispatch targets. For cross-repository PRs (via target-repo), there is no way to configure the base branch of the PR in the target repository.

This prevents workflows that need to create PRs targeting non-default branches in external repos (e.g., a workflow in org/engineering that creates a PR targeting the vnext branch in org/docs).

Expected Behavior

A base-branch field on create-pull-request that lets you specify the target branch for the PR:

safe-outputs:
  create-pull-request:
    draft: true
    target-repo: "microsoft/vscode-docs"
    base-branch: vnext

This should compile to base_branch: "vnext" in the handler config instead of base_branch: "${{ github.ref_name }}".

Actual Behavior

base-branch is not a recognized field — the compiler rejects it:

error: Unknown property: base-branch. Valid fields are: allow-empty, allowed-labels,
allowed-repos, auto-merge, draft, expires, github-token, if-no-changes, labels, reviewers, ...

The base branch is unconditionally set from github.ref_name in the compiled output:

// create_pull_request.go
customEnvVars = append(customEnvVars, "          GH_AW_BASE_BRANCH: \${{ github.ref_name }}\\n")

And the handler config in the lock file reflects this:

{
  "create_pull_request": {
    "base_branch": "${{ github.ref_name }}",
    "target-repo": "microsoft/vscode-docs"
  }
}

Since the workflow is dispatched with ref: main (the branch where the workflow file lives), all cross-repo PRs target main regardless of intent.

Use Case

We're building automation in microsoft/vscode-engineering that triggers when a feature-request issue is closed in microsoft/vscode. It should create two draft PRs in microsoft/vscode-docs:

1. Insiders release notes → targeting main ✅ (works today)
2. Feature documentation → targeting vnext ❌ (no way to configure this)

Both workflows use create-pull-request with target-repo: "microsoft/vscode-docs", but the second one needs to target vnext instead of main.

Source Reference

CreatePullRequestsConfig in pkg/workflow/create_pull_request.go has no BaseBranch field. The env var GH_AW_BASE_BRANCH is unconditionally set to github.ref_name.

Suggested Implementation

Add a BaseBranch field to CreatePullRequestsConfig:

type CreatePullRequestsConfig struct {
    // ...existing fields...
    BaseBranch string `yaml:"base-branch,omitempty"`
}

Then conditionally use it when building the env var:

if data.SafeOutputs.CreatePullRequests.BaseBranch != "" {
    customEnvVars = append(customEnvVars, fmt.Sprintf("          GH_AW_BASE_BRANCH: %q\\n", data.SafeOutputs.CreatePullRequests.BaseBranch))
} else {
    customEnvVars = append(customEnvVars, "          GH_AW_BASE_BRANCH: \${{ github.ref_name }}\\n")
}
```</issue_description>

## Comments on the Issue (you are @copilot in this section)

<comments>
</comments>

• Fixes create-pull-request safe output: add base-branch field for cross-repo PRs targeting non-default branches #15075

---

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[pelikhan]

@copilot Merge main and recompile

[Copilot]

Pull request overview

Adds support for configuring the base branch used by the create-pull-request safe output, enabling cross-repo PR creation targeting non-default branches while keeping the existing ${{ github.ref_name }} default.

Changes:

• Added base-branch to CreatePullRequestsConfig and propagate it into the create PR job env (GH_AW_BASE_BRANCH) and handler-manager config (base_branch).
• Extended the workflow JSON schema to accept the new base-branch field.
• Added unit + integration coverage to validate default vs custom base branch compilation.

Reviewed changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
pkg/workflow/create_pull_request_base_branch_integration_test.go	New integration tests that compile workflows and assert base_branch output for custom/default/slash-containing branches.
pkg/workflow/create_pull_request.go	Adds BaseBranch config field and uses it to set GH_AW_BASE_BRANCH, falling back to ${{ github.ref_name }}.
pkg/workflow/compiler_safe_outputs_config_test.go	Adds unit test verifying handler-manager config JSON includes the expected base_branch.
pkg/workflow/compiler_safe_outputs_config.go	Updates create_pull_request handler config builder to emit custom base_branch or default ${{ github.ref_name }}.
pkg/parser/schemas/main_workflow_schema.json	Adds base-branch to the create-pull-request schema definition.
docs/src/content/docs/reference/frontmatter-full.md	Documents the new base-branch option under safe-outputs.create-pull-request.

---

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[Copilot]

In TestCreatePullRequestBaseBranch, the JSON extraction loop doesn’t assert that it actually found/parses the GH_AW_SAFE_OUTPUTS_HANDLER_CONFIG line. If the env var generation regresses (or the string format changes), the test can pass without validating anything. Track a found boolean (or extract once with SplitN) and require.True(t, found, ...) after the loop, and consider failing if len(parts) != 2 to avoid silent success.

Suggested change

	for _, step := range steps {
	if strings.Contains(step, "GH_AW_SAFE_OUTPUTS_HANDLER_CONFIG") {
	parts := strings.Split(step, "GH_AW_SAFE_OUTPUTS_HANDLER_CONFIG: ")
	if len(parts) == 2 {
	jsonStr := strings.TrimSpace(parts[1])
	jsonStr = strings.Trim(jsonStr, "\"")
	jsonStr = strings.ReplaceAll(jsonStr, "\\\"", "\"")
	var config map[string]map[string]any
	err := json.Unmarshal([]byte(jsonStr), &config)
	require.NoError(t, err, "Config JSON should be valid")
	prConfig, ok := config["create_pull_request"]
	require.True(t, ok, "create_pull_request config should exist")
	baseBranch, ok := prConfig["base_branch"]
	require.True(t, ok, "base_branch should be in config")
	assert.Equal(t, tt.expectedBaseBranch, baseBranch, "base_branch should match expected value")
	}
	}
	}
	found := false
	for _, step := range steps {
	if strings.Contains(step, "GH_AW_SAFE_OUTPUTS_HANDLER_CONFIG") {
	parts := strings.SplitN(step, "GH_AW_SAFE_OUTPUTS_HANDLER_CONFIG: ", 2)
	require.Len(t, parts, 2, "GH_AW_SAFE_OUTPUTS_HANDLER_CONFIG line should contain key and value")
	found = true
	jsonStr := strings.TrimSpace(parts[1])
	jsonStr = strings.Trim(jsonStr, "\"")
	jsonStr = strings.ReplaceAll(jsonStr, "\\\"", "\"")
	var config map[string]map[string]any
	err := json.Unmarshal([]byte(jsonStr), &config)
	require.NoError(t, err, "Config JSON should be valid")
	prConfig, ok := config["create_pull_request"]
	require.True(t, ok, "create_pull_request config should exist")
	baseBranch, ok := prConfig["base_branch"]
	require.True(t, ok, "base_branch should be in config")
	assert.Equal(t, tt.expectedBaseBranch, baseBranch, "base_branch should match expected value")
	}
	}
	require.True(t, found, "GH_AW_SAFE_OUTPUTS_HANDLER_CONFIG should be present in steps")

[Copilot]

@copilot Merge main and recompile

Merged main and recompiled all 148 workflows successfully. The merge combined the base-branch field with the new footer field from main, and all tests pass. Commit: 729952f