fix(plan): use .specify/feature.json to allow /speckit.plan on custom git branches (#2305) (#2349)

* fix: allow plan setup to use feature metadata on custom branches

* fix: harden feature metadata validation

* fix: use portable feature metadata path

Made-with: Cursor

* fix: share feature.json parser and make path compare OS aware

* test: isolate setup plan subprocess environment

* fix: normalize feature metadata paths with pwd -P

scripts/bash/common.sh

@@ -153,6 +153,59 @@ check_feature_branch() {
     return 0
 }
 
+# Safely read .specify/feature.json's "feature_directory" value.
+# Prints the raw value (possibly relative) to stdout, or empty string if the file
+# is missing, unparseable, or does not contain the key. Always returns 0 so callers
+# under `set -e` cannot be aborted by parser failure.
+# Parser order mirrors the historical get_feature_paths behavior: jq -> python3 -> grep/sed.
+read_feature_json_feature_directory() {
+    local repo_root="$1"
+    local fj="$repo_root/.specify/feature.json"
+    [[ -f "$fj" ]] || { printf '%s' ''; return 0; }
+
+    local _fd=''
+    if command -v jq >/dev/null 2>&1; then
+        if ! _fd=$(jq -r '.feature_directory // empty' "$fj" 2>/dev/null); then
+            _fd=''
+        fi
+    elif command -v python3 >/dev/null 2>&1; then
+        # Use Python so pretty-printed/multi-line JSON still parses correctly.
+        if ! _fd=$(python3 -c "import json,sys; d=json.load(open(sys.argv[1])); v=d.get('feature_directory'); print(v if v else '')" "$fj" 2>/dev/null); then
+            _fd=''
+        fi
+    else
+        # Last-resort single-line grep/sed fallback. The `|| true` guards against
+        # grep returning 1 (no match) aborting under `set -e` / `pipefail`.
+        _fd=$( { grep -E '"feature_directory"[[:space:]]*:' "$fj" 2>/dev/null || true; } \
+            | head -n 1 \
+            | sed -E 's/^[^:]*:[[:space:]]*"([^"]*)".*$/\1/' )
+    fi
+
+    printf '%s' "$_fd"
+    return 0
+}
+
+# Returns 0 when .specify/feature.json lists feature_directory that exists as a directory
+# and matches the resolved active FEATURE_DIR (so /speckit.plan can skip git branch pattern checks).
+# Delegates parsing to read_feature_json_feature_directory, which is safe under `set -e`.
+feature_json_matches_feature_dir() {
+    local repo_root="$1"
+    local active_feature_dir="$2"
+
+    local _fd
+    _fd=$(read_feature_json_feature_directory "$repo_root")
+
+    [[ -n "$_fd" ]] || return 1
+    [[ "$_fd" != /* ]] && _fd="$repo_root/$_fd"
+    [[ -d "$_fd" ]] || return 1
+
+    local norm_json norm_active
+    norm_json="$(cd -- "$_fd" 2>/dev/null && pwd -P)" || return 1
+    norm_active="$(cd -- "$active_feature_dir" 2>/dev/null && pwd -P)" || return 1
+
+    [[ "$norm_json" == "$norm_active" ]]
+}
+
 # Find feature directory by numeric prefix instead of exact branch match
 # This allows multiple branches to work on the same spec (e.g., 004-fix-bug, 004-add-feature)
 find_feature_dir_by_prefix() {
@@ -217,16 +270,10 @@ get_feature_paths() {
         # Normalize relative paths to absolute under repo root
         [[ "$feature_dir" != /* ]] && feature_dir="$repo_root/$feature_dir"
     elif [[ -f "$repo_root/.specify/feature.json" ]]; then
+        # Shared, set -e-safe parser: jq -> python3 -> grep/sed. Returns empty on
+        # missing/unparseable/unset so we fall through to the branch-prefix lookup.
         local _fd
-        if command -v jq >/dev/null 2>&1; then
-            _fd=$(jq -r '.feature_directory // empty' "$repo_root/.specify/feature.json" 2>/dev/null)
-        elif command -v python3 >/dev/null 2>&1; then
-            # Fallback: use Python to parse JSON so pretty-printed/multi-line files work
-            _fd=$(python3 -c "import json,sys; d=json.load(open(sys.argv[1])); print(d.get('feature_directory',''))" "$repo_root/.specify/feature.json" 2>/dev/null)
-        else
-            # Last resort: single-line grep fallback (won't work on multi-line JSON)
-            _fd=$(grep -o '"feature_directory"[[:space:]]*:[[:space:]]*"[^"]*"' "$repo_root/.specify/feature.json" 2>/dev/null | sed 's/.*"\([^"]*\)"$/\1/')
-        fi
+        _fd=$(read_feature_json_feature_directory "$repo_root")
         if [[ -n "$_fd" ]]; then
             feature_dir="$_fd"
             # Normalize relative paths to absolute under repo root

scripts/bash/setup-plan.sh

@@ -32,8 +32,10 @@ _paths_output=$(get_feature_paths) || { echo "ERROR: Failed to resolve feature p
 eval "$_paths_output"
 unset _paths_output
 
-# Check if we're on a proper feature branch (only for git repos)
-check_feature_branch "$CURRENT_BRANCH" "$HAS_GIT" || exit 1
+# If feature.json pins an existing feature directory, branch naming is not required.
+if ! feature_json_matches_feature_dir "$REPO_ROOT" "$FEATURE_DIR"; then
+    check_feature_branch "$CURRENT_BRANCH" "$HAS_GIT" || exit 1
+fi
 
 # Ensure the feature directory exists
 mkdir -p "$FEATURE_DIR"

scripts/powershell/common.ps1

@@ -164,6 +164,74 @@ function Test-FeatureBranch {
     return $true
 }
 
+# True when .specify/feature.json pins an existing feature directory that matches the
+# active FEATURE_DIR from Get-FeaturePathsEnv (so /speckit.plan can skip git branch pattern checks).
+function Test-FeatureJsonMatchesFeatureDir {
+    param(
+        [Parameter(Mandatory = $true)][string]$RepoRoot,
+        [Parameter(Mandatory = $true)][string]$ActiveFeatureDir
+    )
+
+    $featureJson = Join-Path (Join-Path $RepoRoot '.specify') 'feature.json'
+    if (-not (Test-Path -LiteralPath $featureJson -PathType Leaf)) {
+        return $false
+    }
+
+    try {
+        $raw = Get-Content -LiteralPath $featureJson -Raw
+        $cfg = $raw | ConvertFrom-Json
+    } catch {
+        return $false
+    }
+
+    $fd = $cfg.feature_directory
+    if ([string]::IsNullOrWhiteSpace([string]$fd)) {
+        return $false
+    }
+
+    if (-not [System.IO.Path]::IsPathRooted($fd)) {
+        $fd = Join-Path $RepoRoot $fd
+    }
+
+    if (-not (Test-Path -LiteralPath $fd -PathType Container)) {
+        return $false
+    }
+
+    # Resolve both paths to canonical absolute form. Prefer Resolve-Path (follows
+    # symlinks and is the canonical PS way); fall back to [Path]::GetFullPath when
+    # Resolve-Path can't produce a value. Mirrors the pattern used by Find-SpecifyRoot.
+    $resolvedJson = Resolve-Path -LiteralPath $fd -ErrorAction SilentlyContinue
+    if ($resolvedJson) {
+        $normJson = $resolvedJson.Path
+    } else {
+        $normJson = [System.IO.Path]::GetFullPath($fd)
+    }
+
+    $resolvedActive = Resolve-Path -LiteralPath $ActiveFeatureDir -ErrorAction SilentlyContinue
+    if ($resolvedActive) {
+        $normActive = $resolvedActive.Path
+    } else {
+        $normActive = [System.IO.Path]::GetFullPath($ActiveFeatureDir)
+    }
+
+    # Use case-insensitive compare only on Windows; POSIX filesystems are case-sensitive.
+    # PowerShell 5.1 is Windows-only and does not define $IsWindows, so treat its
+    # absence as "we're on Windows".
+    if ($null -ne $IsWindows) {
+        $onWindows = $IsWindows
+    } else {
+        $onWindows = $true
+    }
+
+    if ($onWindows) {
+        $comparison = [System.StringComparison]::OrdinalIgnoreCase
+    } else {
+        $comparison = [System.StringComparison]::Ordinal
+    }
+
+    return [string]::Equals($normJson, $normActive, $comparison)
+}
+
 # Resolve specs/<feature-dir> by numeric/timestamp prefix (mirrors scripts/bash/common.sh find_feature_dir_by_prefix).
 function Find-FeatureDirByPrefix {
     param(

scripts/powershell/setup-plan.ps1

@@ -23,9 +23,11 @@ if ($Help) {
 # Get all paths and variables from common functions
 $paths = Get-FeaturePathsEnv
 
-# Check if we're on a proper feature branch (only for git repos)
-if (-not (Test-FeatureBranch -Branch $paths.CURRENT_BRANCH -HasGit $paths.HAS_GIT)) { 
-    exit 1 
+# If feature.json pins an existing feature directory, branch naming is not required.
+if (-not (Test-FeatureJsonMatchesFeatureDir -RepoRoot $paths.REPO_ROOT -ActiveFeatureDir $paths.FEATURE_DIR)) {
+    if (-not (Test-FeatureBranch -Branch $paths.CURRENT_BRANCH -HasGit $paths.HAS_GIT)) {
+        exit 1
+    }
 }
 
 # Ensure the feature directory exists