feat: make git extension opt-in and remove --no-git at v0.10.0 (#2873)

* feat(init)!: make git extension opt-in and remove --no-git at v0.10.0

- Remove --no-git parameter from specify init command
- Remove git extension auto-installation from init flow
- Git repository initialization (git init) still runs when git is available
- Remove --no-git from all test invocations across the test suite
- Update docs to reflect opt-in git extension behavior
- Replace TestGitExtensionAutoInstall with TestGitExtensionOptIn tests

BREAKING CHANGE: specify init no longer auto-installs the git extension.
Use `specify extension add git` to install it explicitly.
The --no-git flag has been removed.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

* refactor(scripts): remove git operations from core scripts

Git functionality is now entirely managed by the git extension.
Core scripts only handle directory-based feature creation and numbering.

- Remove has_git(), check_feature_branch(), git branch creation from core
- Simplify number detection to use only spec directory scanning
- Remove HAS_GIT output from get_feature_paths()
- Remove git remote fetching and branch querying
- Keep BRANCH_NAME output key for backward compatibility

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

* refactor: remove all git operations from core

- Remove is_git_repo() and init_git_repo() dead code from _utils.py
- Remove --branch-numbering from init command
- Remove git from 'specify check' (now extension-only)
- Update docs: git is optional prerequisite, check command description
- Fix tests to reflect no-git-in-core reality (fallback to main)

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

* refactor(scripts): remove directory scanning and branch fallback from core

Core scripts now resolve feature context exclusively from:
1. SPECIFY_FEATURE env var (set by git extension)
2. .specify/feature.json (persisted by specify command)

Removed find_feature_dir_by_prefix() and directory scanning heuristics —
these are the git extension's responsibility. Scripts error clearly when
no feature context is available.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

* feat: introduce feature_numbering, deprecate branch_numbering in init-options

- specify command template now reads feature_numbering (preferred) with
  fallback to branch_numbering (deprecated) from init-options.json
- Git extension reads git-config.yml > feature_numbering > branch_numbering
- init now writes feature_numbering: sequential to init-options.json
- Deprecation warning emitted when branch_numbering is used as fallback

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

* fix: remove trailing whitespace in common.ps1

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

* feat(scripts): persist SPECIFY_FEATURE_DIRECTORY env var to feature.json

When SPECIFY_FEATURE_DIRECTORY is set, get_feature_paths() now writes the
value to .specify/feature.json so future sessions without the env var can
still resolve the feature directory. The write is idempotent — it skips
when the file already contains the same value.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

* fix: address review feedback — error messages and docs

- Update error messages in common.sh and common.ps1 to reference
  SPECIFY_FEATURE_DIRECTORY instead of SPECIFY_FEATURE (which no longer
  resolves feature directories)
- Fix get_current_branch comment (returns empty string, not error)
- Update upgrade.md to reference SPECIFY_FEATURE_DIRECTORY with correct
  example paths
- Update local-development.md troubleshooting: replace stale 'Git step
  skipped' row with actionable git extension guidance

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

* fix(scripts): harden feature.json persistence

- Use json_escape in printf fallback when jq is unavailable (common.sh)
- Replace utf8NoBOM encoding with UTF8Encoding($false) for PowerShell
  5.1 compatibility (common.ps1)

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

* refactor(scripts): remove dead feature_json_matches_feature_dir functions

These guards are no longer needed since the branch-name validation they
protected against has been removed from check-prerequisites.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

* refactor(git-ext): rename create-new-feature to create-new-feature-branch

The git extension's script only creates the git branch — rename it to
reflect that responsibility. The core create-new-feature.sh/.ps1 handles
feature directory creation and feature.json persistence.

Also includes fixes from review feedback:
- common.sh: _persist_feature_json uses json_escape fallback
- common.ps1: Save-FeatureJson uses UTF8Encoding for PS 5.1 compat
- common.ps1: case-sensitive path stripping on non-Windows
- create-new-feature.sh/ps1: output both SPECIFY_FEATURE and
  SPECIFY_FEATURE_DIRECTORY
- setup-tasks.sh: fix stale 'Validate branch' comment

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

* fix(tests): update references to renamed git extension scripts

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

* fix(tests): remove duplicate EXT_CREATE_FEATURE assignments

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

---------

Co-authored-by: Manfred Riem <mnriem@users.noreply.github.com>
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

extensions/git/README.md

@@ -94,7 +94,7 @@ When Git is not installed or the directory is not a Git repository:
 
 The extension bundles cross-platform scripts:
 
-- `scripts/bash/create-new-feature.sh` — Bash implementation
+- `scripts/bash/create-new-feature-branch.sh` — Bash implementation (branch creation only)
 - `scripts/bash/git-common.sh` — Shared Git utilities (Bash)
-- `scripts/powershell/create-new-feature.ps1` — PowerShell implementation
+- `scripts/powershell/create-new-feature-branch.ps1` — PowerShell implementation (branch creation only)
 - `scripts/powershell/git-common.ps1` — Shared Git utilities (PowerShell)

extensions/git/commands/speckit.git.feature.md

@@ -31,8 +31,9 @@ If the user explicitly provided `GIT_BRANCH_NAME` (e.g., via environment variabl
 Determine the branch numbering strategy by checking configuration in this order:
 
 1. Check `.specify/extensions/git/git-config.yml` for `branch_numbering` value
-2. Check `.specify/init-options.json` for `branch_numbering` value (backward compatibility)
-3. Default to `sequential` if neither exists
+2. Check `.specify/init-options.json` for `feature_numbering` value (inherit from core)
+3. Check `.specify/init-options.json` for `branch_numbering` value (deprecated, backward compatibility — will be removed in a future release)
+4. Default to `sequential` if none of the above exist
 
 ## Execution
 
@@ -43,10 +44,10 @@ Generate a concise short name (2-4 words) for the branch:
 
 Run the appropriate script based on your platform:
 
-- **Bash**: `.specify/extensions/git/scripts/bash/create-new-feature.sh --json --short-name "<short-name>" "<feature description>"`
-- **Bash (timestamp)**: `.specify/extensions/git/scripts/bash/create-new-feature.sh --json --timestamp --short-name "<short-name>" "<feature description>"`
-- **PowerShell**: `.specify/extensions/git/scripts/powershell/create-new-feature.ps1 -Json -ShortName "<short-name>" "<feature description>"`
-- **PowerShell (timestamp)**: `.specify/extensions/git/scripts/powershell/create-new-feature.ps1 -Json -Timestamp -ShortName "<short-name>" "<feature description>"`
+- **Bash**: `.specify/extensions/git/scripts/bash/create-new-feature-branch.sh --json --short-name "<short-name>" "<feature description>"`
+- **Bash (timestamp)**: `.specify/extensions/git/scripts/bash/create-new-feature-branch.sh --json --timestamp --short-name "<short-name>" "<feature description>"`
+- **PowerShell**: `.specify/extensions/git/scripts/powershell/create-new-feature-branch.ps1 -Json -ShortName "<short-name>" "<feature description>"`
+- **PowerShell (timestamp)**: `.specify/extensions/git/scripts/powershell/create-new-feature-branch.ps1 -Json -Timestamp -ShortName "<short-name>" "<feature description>"`
 
 **IMPORTANT**:
 - Do NOT pass `--number` — the script determines the correct next number automatically

extensions/git/scripts/bash/create-new-feature-branch.sh

@@ -1,6 +1,7 @@
 #!/usr/bin/env bash
-# Git extension: create-new-feature.sh
-# Adapted from core scripts/bash/create-new-feature.sh for extension layout.
+# Git extension: create-new-feature-branch.sh
+# Creates a git feature branch only. The feature directory and spec file
+# are created by the core create-new-feature.sh script.
 # Sources common.sh from the project's installed scripts, falling back to
 # git-common.sh for minimal git helpers.
 

extensions/git/scripts/powershell/create-new-feature-branch.ps1

@@ -1,6 +1,7 @@
 #!/usr/bin/env pwsh
-# Git extension: create-new-feature.ps1
-# Adapted from core scripts/powershell/create-new-feature.ps1 for extension layout.
+# Git extension: create-new-feature-branch.ps1
+# Creates a git feature branch only. The feature directory and spec file
+# are created by the core create-new-feature.ps1 script.
 # Sources common.ps1 from the project's installed scripts, falling back to
 # git-common.ps1 for minimal git helpers.
 [CmdletBinding()]
@@ -19,7 +20,7 @@ param(
 $ErrorActionPreference = 'Stop'
 
 if ($Help) {
-    Write-Host "Usage: ./create-new-feature.ps1 [-Json] [-DryRun] [-AllowExistingBranch] [-ShortName <name>] [-Number N] [-Timestamp] <feature description>"
+    Write-Host "Usage: ./create-new-feature-branch.ps1 [-Json] [-DryRun] [-AllowExistingBranch] [-ShortName <name>] [-Number N] [-Timestamp] <feature description>"
     Write-Host ""
     Write-Host "Options:"
     Write-Host "  -Json               Output in JSON format"
@@ -37,7 +38,7 @@ if ($Help) {
 }
 
 if (-not $FeatureDescription -or $FeatureDescription.Count -eq 0) {
-    Write-Error "Usage: ./create-new-feature.ps1 [-Json] [-DryRun] [-AllowExistingBranch] [-ShortName <name>] [-Number N] [-Timestamp] <feature description>"
+    Write-Error "Usage: ./create-new-feature-branch.ps1 [-Json] [-DryRun] [-AllowExistingBranch] [-ShortName <name>] [-Number N] [-Timestamp] <feature description>"
     exit 1
 }