You are implementing Task 17 of the birdseye CLI implementation plan.

## Working Environment

- **Worktree path:** `/Users/steve.briggs/projects/operations/.claude/worktrees/birdseye`
- **Git branch:** `worktree-birdseye`
- Recent commits include Task 16 semantic diff (`b914c7c`).
- Use absolute paths or `cd` into the worktree.
- **NEVER push.** **NEVER use `git add .` / `git add -A`.**

## Context

Task 16 added `diff.Semantic` and the `--semantic` flag is already registered on `newDiffCmd` (Task 10). Your job: wire the flag into `runDiff` so it calls `diff.Semantic` and stores the results in `diff.Result.Semantic`, and extend `renderPlain` to print a "=== semantic changes ===" section after the textual diff. Add a test that asserts the semantic output contains the expected entries.

## Task Description (Verbatim)

### Task 17: Wire `--semantic` flag into `cmd diff` and renderers

**Files:**
- Modify: `apps/birdseye/cmd/diff.go`
- Modify: `apps/birdseye/cmd/diff_test.go`

- [ ] **Step 1: Append failing test** to `apps/birdseye/cmd/diff_test.go`:

```go
func TestDiffSemanticIncluded(t *testing.T) {
	srv := fakeCrowTwoVersions(t)
	root := NewRootCmd()
	var stdout bytes.Buffer
	root.SetOut(&stdout)
	root.SetArgs([]string{
		"diff",
		"iac/comply/aws", "1.0.0", "1.1.0",
		"--crow-url", srv.URL,
		"--plain",
		"--semantic",
		"--cache-dir", t.TempDir(),
	})
	if err := root.ExecuteContext(context.Background()); err != nil {
		t.Fatalf("execute: %v", err)
	}
	out := stdout.String()
	for _, want := range []string{
		"=== semantic changes ===",
		"resource",
		"aws_s3_bucket.alpha",
		"aws_s3_bucket.beta",
		"variable",
		"name",
	} {
		if !strings.Contains(out, want) {
			t.Errorf("semantic output missing %q\n--- output ---\n%s", want, out)
		}
	}
}
```

- [ ] **Step 2: Run, expect FAIL** (semantic block not produced)

Run: `cd /Users/steve.briggs/projects/operations/.claude/worktrees/birdseye/apps/birdseye && go test ./cmd/... -run TestDiffSemantic -v`
Expected: failure — semantic content not in output.

- [ ] **Step 3: Update `runDiff`** in `apps/birdseye/cmd/diff.go`:

Find this block (around the end of `runDiff`):

```go
	result := diff.Result{Files: diff.Textual(modAExtracted, modBExtracted)}
	// Semantic mode wired in Task 17.
	// TUI mode wired in Task 13.
```

Replace with:

```go
	result := diff.Result{Files: diff.Textual(modAExtracted, modBExtracted)}
	if o.Semantic {
		sem, err := diff.Semantic(modAExtracted, modBExtracted)
		if err != nil {
			return fmt.Errorf("%w: %v", ErrSemantic, err)
		}
		result.Semantic = sem
	}
```

(The comment about TUI mode being wired in Task 13 — that's already done. Drop both stale comments.)

- [ ] **Step 4: Extend `renderPlain`** in `apps/birdseye/cmd/diff.go`:

Replace the `renderPlain` body:

```go
func renderPlain(w io.Writer, r diff.Result) error {
	if len(r.Files) == 0 && len(r.Semantic) == 0 {
		_, err := fmt.Fprintln(w, "no differences")
		return err
	}
	for i, fd := range r.Files {
		if i > 0 {
			_, _ = fmt.Fprintln(w)
		}
		_, _ = fmt.Fprintf(w, "=== %s (%s) +%d -%d\n", fd.Path, fd.Status, fd.Adds, fd.Dels)
		_, _ = fmt.Fprint(w, fd.Unified)
	}
	if len(r.Semantic) > 0 {
		_, _ = fmt.Fprintln(w)
		_, _ = fmt.Fprintln(w, "=== semantic changes ===")
		for _, c := range r.Semantic {
			_, _ = fmt.Fprintf(w, "%s %s %s\n", c.Status, c.Kind, c.Name)
		}
	}
	return nil
}
```

- [ ] **Step 5: Run, expect PASS**

Run: `cd /Users/steve.briggs/projects/operations/.claude/worktrees/birdseye/apps/birdseye && go test -race ./... -v`
Expected: All PASS, including `TestDiffSemanticIncluded`.

- [ ] **Step 6: Commit**

```bash
cd /Users/steve.briggs/projects/operations/.claude/worktrees/birdseye && git add apps/birdseye/cmd/ && git commit -m "feat(birdseye): --semantic flag wired into one-shot diff output"
```

## Notes & Style

- Don't add new flags. `--semantic` already exists (Task 10).
- The "no differences" path needs to consider BOTH `Files` and `Semantic` — if either is non-empty, render the appropriate section.
- ErrSemantic wraps the HCL parse error so exit code becomes 5.
- The output format for semantic entries is `<status> <kind> <name>` (e.g., `added resource aws_s3_bucket.beta`). Match exactly so the test passes.

## Self-Review Checklist

- [ ] `TestDiffSemanticIncluded` passes
- [ ] Previous `TestDiffIdenticalVersionsNoChanges` STILL passes (i.e., `no differences` still prints when both Files and Semantic are empty)
- [ ] All other tests pass under `-race`
- [ ] `go vet ./...` clean
- [ ] `go build ./...` succeeds
- [ ] ErrSemantic wrapped on parse failure
- [ ] Commit message exactly: `feat(birdseye): --semantic flag wired into one-shot diff output`

## Report Format

- **Status:** DONE | DONE_WITH_CONCERNS | BLOCKED | NEEDS_CONTEXT
- Files modified
- Test count + race-clean
- Commit SHA
- Anything unexpected


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I'll implement Task 17 by following the steps precisely. Let me start by reading the relevant files.


1	package cmd
2
3	import (
4		"context"
5		"fmt"
6		"io"
7		"net/http"
8		"os"
9		"path/filepath"
10		"strings"
11		"time"
12
13		tea "github.com/charmbracelet/bubbletea"
14		"github.com/spf13/cobra"
15		"golang.org/x/term"
16
17		"github.com/immuta/operations/apps/birdseye/internal/archive"
18		"github.com/immuta/operations/apps/birdseye/internal/diff"
19		"github.com/immuta/operations/apps/birdseye/internal/registry"
20		"github.com/immuta/operations/apps/birdseye/internal/tui"
21		"github.com/immuta/operations/services/crow/pkg/api"
22		"github.com/immuta/operations/services/crow/pkg/client"
23	)
24
25	// diffOpts holds the resolved options for `birdseye diff`.
26	type diffOpts struct {
27		Semantic bool
28		Plain    bool
29		CacheDir string
30	}
31
32	const maxArchiveBytes = 50 << 20 // 50 MiB safety cap on uncompressed size
33
34	func newDiffCmd(g *GlobalFlags) *cobra.Command {
35		o := &diffOpts{}
36		c := &cobra.Command{
37			Use:   "diff [module] [versionA] [versionB]",
38			Short: "Diff two versions of a Crow module",
39			Long: "Diff two versions of a module hosted in Crow.\n\n" +
40				"If module/versions are omitted, the interactive TUI launches\n" +
41				"(see picker task). With --plain, prints unified diff to stdout.",
42			Args:          cobra.MaximumNArgs(3),
43			SilenceUsage:  true,
44			SilenceErrors: true,
45			RunE: func(cmd *cobra.Command, args []string) error {
46				return runDiff(cmd.Context(), cmd, args, g, o)
47			},
48		}
49		c.Flags().BoolVar(&o.Semantic, "semantic", false, "include HCL-aware semantic diff alongside textual")
50		c.Flags().BoolVar(&o.Plain, "plain", false, "force plain (non-TUI) output")
51		c.Flags().BoolVar(&o.Plain, "no-tui", false, "alias for --plain")
52		c.Flags().StringVar(&o.CacheDir, "cache-dir", defaultCacheDir(), "module tarball cache directory")
53		return c
54	}
55
56	func defaultCacheDir() string {
57		if home, err := os.UserCacheDir(); err == nil {
58			return filepath.Join(home, "birdseye")
59		}
60		return ".birdseye-cache"
61	}
62
63	func newHTTPClient(d time.Duration) *http.Client {
64		return &http.Client{Timeout: d}
65	}
66
67	func parseModuleAddress(s string) (api.ModuleIdentifier, error) {
68		parts := strings.Split(s, "/")
69		if len(parts) != 3 {
70			return api.ModuleIdentifier{}, fmt.Errorf("%w: module address must be namespace/name/provider, got %q", ErrUsage, s)
71		}
72		id := api.ModuleIdentifier{Namespace: parts[0], Name: parts[1], Provider: parts[2]}
73		if err := id.Validate(); err != nil {
74			return api.ModuleIdentifier{}, fmt.Errorf("%w: %v", ErrUsage, err)
75		}
76		return id, nil
77	}
78
79	func runDiff(ctx context.Context, cmd *cobra.Command, args []string, g *GlobalFlags, o *diffOpts) error {
80		if len(args) == 0 {
81			return runInteractive(ctx, cmd, g, o)
82		}
83		if len(args) != 3 {
84			return fmt.Errorf("%w: diff requires <module> <versionA> <versionB>", ErrUsage)
85		}
86		id, err := parseModuleAddress(args[0])
87		if err != nil {
88			return err
89		}
90		if err := api.ValidateVersion(args[1]); err != nil {
91			return fmt.Errorf("%w: %v", ErrUsage, err)
92		}
93		if err := api.ValidateVersion(args[2]); err != nil {
94			return fmt.Errorf("%w: %v", ErrUsage, err)
95		}
96		modA := api.Module{ModuleIdentifier: id, Version: args[1]}
97		modB := api.Module{ModuleIdentifier: id, Version: args[2]}
98
99		cli := client.New(g.CrowURL, client.WithHTTPClient(newHTTPClient(g.Timeout)))
100		cache, err := registry.NewDiskCache(o.CacheDir)
101		if err != nil {
102			return fmt.Errorf("cache init: %w", err)
103		}
104		reg := registry.New(cli, cache)
105
106		aBytes, bBytes, err := reg.FetchPair(ctx, modA, modB)
107		if err != nil {
108			return err
109		}
110
111		modAExtracted, err := archive.Extract(aBytes, maxArchiveBytes)
112		if err != nil {
113			return fmt.Errorf("%w: %v", ErrArchive, err)
114		}
115		modBExtracted, err := archive.Extract(bBytes, maxArchiveBytes)
116		if err != nil {
117			return fmt.Errorf("%w: %v", ErrArchive, err)
118		}
119
120		result := diff.Result{Files: diff.Textual(modAExtracted, modBExtracted)}
121		// Semantic mode wired in Task 17.
122
123		if !o.Plain && isTTY(cmd.OutOrStdout()) {
124			return tui.RunBrowser(ctx, result)
125		}
126		return renderPlain(cmd.OutOrStdout(), result)
127	}
128
129	// isTTY reports whether w is a *os.File backed by a terminal.
130	func isTTY(w io.Writer) bool {
131		f, ok := w.(*os.File)
132		if !ok {
133			return false
134		}
135		return term.IsTerminal(int(f.Fd()))
136	}
137
138	func runInteractive(ctx context.Context, cmd *cobra.Command, g *GlobalFlags, o *diffOpts) error {
139		if !isTTY(cmd.OutOrStdout()) {
140			return fmt.Errorf("%w: interactive mode requires a TTY", ErrUsage)
141		}
142		cli := client.New(g.CrowURL, client.WithHTTPClient(newHTTPClient(g.Timeout)))
143		cache, err := registry.NewDiskCache(o.CacheDir)
144		if err != nil {
145			return fmt.Errorf("cache init: %w", err)
146		}
147		reg := registry.New(cli, cache)
148
149		// Stage 1: picker → fetched bytes
150		p := tui.NewPicker(&tui.Deps{Client: cli, Reg: reg})
151		prog := tea.NewProgram(p, tea.WithAltScreen(), tea.WithContext(ctx))
152		if _, err := prog.Run(); err != nil {
153			return err
154		}
155		aBytes, bBytes := p.Bytes()
156		if aBytes == nil || bBytes == nil {
157			// User quit before completing picker; not an error.
158			return nil
159		}
160
161		// Stage 2: extract + diff + browser
162		modA, err := archive.Extract(aBytes, maxArchiveBytes)
163		if err != nil {
164			return fmt.Errorf("%w: %v", ErrArchive, err)
165		}
166		modB, err := archive.Extract(bBytes, maxArchiveBytes)
167		if err != nil {
168			return fmt.Errorf("%w: %v", ErrArchive, err)
169		}
170		result := diff.Result{Files: diff.Textual(modA, modB)}
171		return tui.RunBrowser(ctx, result)
172	}
173
174	// renderPlain writes the diff result to w in unified-diff format.
175	// "no differences" is emitted when there are zero files in the result.
176	func renderPlain(w io.Writer, r diff.Result) error {
177		if len(r.Files) == 0 {
178			_, err := fmt.Fprintln(w, "no differences")
179			return err
180		}
181		for i, fd := range r.Files {
182			if i > 0 {
183				_, _ = fmt.Fprintln(w)
184			}
185			_, _ = fmt.Fprintf(w, "=== %s (%s) +%d -%d\n", fd.Path, fd.Status, fd.Adds, fd.Dels)
186			_, _ = fmt.Fprint(w, fd.Unified)
187		}
188		return nil
189	}
190


1	package cmd
2
3	import (
4		"archive/tar"
5		"bytes"
6		"compress/gzip"
7		"context"
8		"net/http"
9		"net/http/httptest"
10		"strings"
11		"testing"
12	)
13
14	// fakeCrow with two versions of moduleA. v1 has main.tf; v2 has main.tf
15	// (modified) and a new variables.tf.
16	func fakeCrowTwoVersions(t *testing.T) *httptest.Server {
17		t.Helper()
18		mkTgz := func(files map[string]string) []byte {
19			var buf bytes.Buffer
20			gz := gzip.NewWriter(&buf)
21			tw := tar.NewWriter(gz)
22			for n, b := range files {
23				_ = tw.WriteHeader(&tar.Header{Name: n, Mode: 0o644, Size: int64(len(b)), Typeflag: tar.TypeReg})
24				_, _ = tw.Write([]byte(b))
25			}
26			_ = tw.Close()
27			_ = gz.Close()
28			return buf.Bytes()
29		}
30		v1 := mkTgz(map[string]string{"main.tf": "resource \"aws_s3_bucket\" \"alpha\" {}\n"})
31		v2 := mkTgz(map[string]string{
32			"main.tf":      "resource \"aws_s3_bucket\" \"beta\" {}\n",
33			"variables.tf": "variable \"name\" { type = string }\n",
34		})
35
36		mux := http.NewServeMux()
37		blob := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
38			switch r.URL.Path {
39			case "/blob/1.0.0":
40				_, _ = w.Write(v1)
41			case "/blob/1.1.0":
42				_, _ = w.Write(v2)
43			default:
44				http.NotFound(w, r)
45			}
46		}))
47		t.Cleanup(blob.Close)
48		mux.HandleFunc("/v1/modules/iac/comply/aws/", func(w http.ResponseWriter, r *http.Request) {
49			parts := strings.Split(strings.TrimPrefix(r.URL.Path, "/v1/modules/iac/comply/aws/"), "/")
50			if len(parts) != 2 || parts[1] != "download" {
51				http.NotFound(w, r)
52				return
53			}
54			w.Header().Set("X-Terraform-Get", blob.URL+"/blob/"+parts[0])
55			w.WriteHeader(http.StatusNoContent)
56		})
57		srv := httptest.NewServer(mux)
58		t.Cleanup(srv.Close)
59		return srv
60	}
61
62	func TestDiffPlainOutput(t *testing.T) {
63		srv := fakeCrowTwoVersions(t)
64		root := NewRootCmd()
65		var stdout, stderr bytes.Buffer
66		root.SetOut(&stdout)
67		root.SetErr(&stderr)
68		root.SetArgs([]string{
69			"diff",
70			"iac/comply/aws", "1.0.0", "1.1.0",
71			"--crow-url", srv.URL,
72			"--plain",
73			"--cache-dir", t.TempDir(),
74		})
75		if err := root.ExecuteContext(context.Background()); err != nil {
76			t.Fatalf("execute: %v\nstderr: %s", err, stderr.String())
77		}
78		out := stdout.String()
79		for _, want := range []string{"main.tf", "variables.tf", "alpha", "beta"} {
80			if !strings.Contains(out, want) {
81				t.Errorf("plain output missing %q\n--- output ---\n%s", want, out)
82			}
83		}
84	}
85
86	func TestDiffIdenticalVersionsNoChanges(t *testing.T) {
87		srv := fakeCrowTwoVersions(t)
88		root := NewRootCmd()
89		var stdout bytes.Buffer
90		root.SetOut(&stdout)
91		root.SetArgs([]string{
92			"diff",
93			"iac/comply/aws", "1.0.0", "1.0.0",
94			"--crow-url", srv.URL,
95			"--plain",
96			"--cache-dir", t.TempDir(),
97		})
98		if err := root.ExecuteContext(context.Background()); err != nil {
99			t.Fatalf("execute: %v", err)
100		}
101		if got := strings.TrimSpace(stdout.String()); got != "no differences" {
102			t.Errorf("output = %q, want \"no differences\"", got)
103		}
104	}
105
106	func TestDiffBadModuleAddress(t *testing.T) {
107		root := NewRootCmd()
108		var stderr bytes.Buffer
109		root.SetErr(&stderr)
110		root.SetArgs([]string{"diff", "bad-address", "1.0.0", "1.1.0"})
111		err := root.ExecuteContext(context.Background())
112		if err == nil {
113			t.Fatal("expected error for bad address")
114		}
115		if ExitCode(err) != 1 {
116			t.Errorf("exit code = %d, want 1", ExitCode(err))
117		}
118	}
119


Now let me look at the diff package to understand the Semantic function and Result struct:


Error: EISDIR: illegal operation on a directory, read '/Users/steve.briggs/projects/operations/.claude/worktrees/birdseye/apps/birdseye/internal/diff'


Bash

List diff package files


.rw-r--r-- steve.briggs staff 2.2 KB Tue May 12 23:39:29 2026 textual_test.go
.rw-r--r-- steve.briggs staff 1.1 KB Tue May 12 23:39:42 2026 types.go
.rw-r--r-- steve.briggs staff 2.6 KB Tue May 12 23:44:54 2026 textual.go
drwxr-xr-x steve.briggs staff 192 B  Tue May 12 23:55:20 2026 ..
.rw-r--r-- steve.briggs staff 1.8 KB Wed May 13 00:19:39 2026 semantic_test.go
.rw-r--r-- steve.briggs staff 5.6 KB Wed May 13 00:20:17 2026 semantic.go
drwxr-xr-x steve.briggs staff 224 B  Wed May 13 00:20:17 2026 .


1	// Package diff produces FileDiff entries and optional SemanticChange
2	// entries from a pair of extracted Modules. All functions are pure: no
3	// I/O, no globals.
4	package diff
5
6	// FileStatus describes what happened to a file between the two versions.
7	type FileStatus int
8
9	const (
10		StatusModified FileStatus = iota
11		StatusAdded
12		StatusRemoved
13	)
14
15	func (s FileStatus) String() string {
16		switch s {
17		case StatusAdded:
18			return "added"
19		case StatusRemoved:
20			return "removed"
21		default:
22			return "modified"
23		}
24	}
25
26	// FileDiff is a per-file diff result. Unified holds the rendered diff
27	// hunks; Adds/Dels are the count of added/removed lines for summary
28	// rendering.
29	type FileDiff struct {
30		Path    string
31		Status  FileStatus
32		Unified string
33		Adds    int
34		Dels    int
35	}
36
37	// SemanticChange is a single HCL-aware change. Kind is one of "resource",
38	// "variable", "output", "provider", "locals", "data", or "module".
39	type SemanticChange struct {
40		Kind   string
41		Name   string
42		Status FileStatus
43		Detail string
44	}
45
46	// Result is what cmd/diff renders. Semantic is nil unless --semantic was
47	// requested.
48	type Result struct {
49		Files    []FileDiff
50		Semantic []SemanticChange
51	}
52


1	package diff
2
3	import (
4		"crypto/sha256"
5		"encoding/hex"
6		"errors"
7		"fmt"
8		"sort"
9		"strings"
10
11		"github.com/hashicorp/hcl/v2"
12		"github.com/hashicorp/hcl/v2/hclparse"
13		"github.com/hashicorp/hcl/v2/hclsyntax"
14
15		"github.com/immuta/operations/apps/birdseye/internal/archive"
16	)
17
18	// ErrParseFailed is returned by Semantic when any .tf file fails to
19	// parse. Callers map this to exit code 5.
20	var ErrParseFailed = errors.New("hcl parse failed")
21
22	// blockEntry pairs an HCL block with the source bytes of its file so
23	// that blockHash can read actual expression text rather than byte offsets.
24	type blockEntry struct {
25		block *hclsyntax.Block
26		src   []byte
27	}
28
29	// ModuleSummary aggregates the named HCL blocks of interest from every
30	// .tf file in a module. Maps are keyed by a stable identifier
31	// (resource: "type.name", variable: name, etc.).
32	type ModuleSummary struct {
33		Resources map[string]blockEntry
34		Variables map[string]blockEntry
35		Outputs   map[string]blockEntry
36		Providers map[string]blockEntry
37		Locals    map[string]blockEntry
38		Data      map[string]blockEntry
39		Modules   map[string]blockEntry
40	}
41
42	// Semantic produces SemanticChange entries by parsing every .tf file in
43	// each archive into a ModuleSummary and diffing summaries.
44	func Semantic(a, b archive.Module) ([]SemanticChange, error) {
45		sa, err := summarize(a)
46		if err != nil {
47			return nil, err
48		}
49		sb, err := summarize(b)
50		if err != nil {
51			return nil, err
52		}
53		var out []SemanticChange
54		out = append(out, diffMap("resource", sa.Resources, sb.Resources)...)
55		out = append(out, diffMap("variable", sa.Variables, sb.Variables)...)
56		out = append(out, diffMap("output", sa.Outputs, sb.Outputs)...)
57		out = append(out, diffMap("provider", sa.Providers, sb.Providers)...)
58		out = append(out, diffMap("locals", sa.Locals, sb.Locals)...)
59		out = append(out, diffMap("data", sa.Data, sb.Data)...)
60		out = append(out, diffMap("module", sa.Modules, sb.Modules)...)
61		sort.SliceStable(out, func(i, j int) bool {
62			if out[i].Kind != out[j].Kind {
63				return out[i].Kind < out[j].Kind
64			}
65			return out[i].Name < out[j].Name
66		})
67		return out, nil
68	}
69
70	func summarize(m archive.Module) (ModuleSummary, error) {
71		s := ModuleSummary{
72			Resources: map[string]blockEntry{},
73			Variables: map[string]blockEntry{},
74			Outputs:   map[string]blockEntry{},
75			Providers: map[string]blockEntry{},
76			Locals:    map[string]blockEntry{},
77			Data:      map[string]blockEntry{},
78			Modules:   map[string]blockEntry{},
79		}
80		parser := hclparse.NewParser()
81		for path, body := range m.Files {
82			if !strings.HasSuffix(path, ".tf") {
83				continue
84			}
85			file, diags := parser.ParseHCL(body, path)
86			if diags.HasErrors() {
87				return ModuleSummary{}, fmt.Errorf("%w: %s: %s", ErrParseFailed, path, diags.Error())
88			}
89			syntaxBody, ok := file.Body.(*hclsyntax.Body)
90			if !ok {
91				return ModuleSummary{}, fmt.Errorf("%w: %s: unexpected body type", ErrParseFailed, path)
92			}
93			for _, blk := range syntaxBody.Blocks {
94				key, target := classify(blk, &s)
95				if target == nil {
96					continue
97				}
98				target[key] = blockEntry{block: blk, src: body}
99			}
100		}
101		return s, nil
102	}
103
104	func classify(blk *hclsyntax.Block, s *ModuleSummary) (string, map[string]blockEntry) {
105		switch blk.Type {
106		case "resource":
107			if len(blk.Labels) != 2 {
108				return "", nil
109			}
110			return blk.Labels[0] + "." + blk.Labels[1], s.Resources
111		case "data":
112			if len(blk.Labels) != 2 {
113				return "", nil
114			}
115			return blk.Labels[0] + "." + blk.Labels[1], s.Data
116		case "module":
117			if len(blk.Labels) != 1 {
118				return "", nil
119			}
120			return blk.Labels[0], s.Modules
121		case "variable":
122			if len(blk.Labels) != 1 {
123				return "", nil
124			}
125			return blk.Labels[0], s.Variables
126		case "output":
127			if len(blk.Labels) != 1 {
128				return "", nil
129			}
130			return blk.Labels[0], s.Outputs
131		case "provider":
132			if len(blk.Labels) != 1 {
133				return "", nil
134			}
135			return blk.Labels[0], s.Providers
136		case "locals":
137			// `locals` has no labels and may appear in multiple files;
138			// distinguish by source range so we don't collide.
139			return blk.Range().Filename + "#" + fmt.Sprint(blk.Range().Start.Line), s.Locals
140		}
141		return "", nil
142	}
143
144	func diffMap(kind string, a, b map[string]blockEntry) []SemanticChange {
145		var out []SemanticChange
146		for name, ae := range a {
147			be, ok := b[name]
148			if !ok {
149				out = append(out, SemanticChange{Kind: kind, Name: name, Status: StatusRemoved})
150				continue
151			}
152			if blockHash(ae) != blockHash(be) {
153				out = append(out, SemanticChange{Kind: kind, Name: name, Status: StatusModified})
154			}
155		}
156		for name := range b {
157			if _, ok := a[name]; !ok {
158				out = append(out, SemanticChange{Kind: kind, Name: name, Status: StatusAdded})
159			}
160		}
161		return out
162	}
163
164	// blockHash digests the content of a block using actual source bytes for
165	// attribute expressions. Equal hashes mean byte-identical attribute values
166	// so any change to an attribute value will shift the hash.
167	func blockHash(e blockEntry) string {
168		blk := e.block
169		src := e.src
170		h := sha256.New()
171		h.Write([]byte(strings.Join(blk.Labels, "|")))
172		keys := make([]string, 0, len(blk.Body.Attributes))
173		for k := range blk.Body.Attributes {
174			keys = append(keys, k)
175		}
176		sort.Strings(keys)
177		for _, k := range keys {
178			attr := blk.Body.Attributes[k]
179			h.Write([]byte(k))
180			h.Write([]byte{0})
181			h.Write([]byte(exprText(src, attr.Expr.Range())))
182			h.Write([]byte{0})
183		}
184		for _, nested := range blk.Body.Blocks {
185			h.Write([]byte(nested.Type))
186			h.Write([]byte{0})
187			h.Write([]byte(strings.Join(nested.Labels, "|")))
188			h.Write([]byte{0})
189		}
190		return hex.EncodeToString(h.Sum(nil))
191	}
192
193	// exprText returns the actual source bytes of an expression's range.
194	func exprText(src []byte, r hcl.Range) string {
195		if r.End.Byte > len(src) || r.Start.Byte > r.End.Byte {
196			return fmt.Sprintf("%d:%d", r.Start.Byte, r.End.Byte)
197		}
198		return string(src[r.Start.Byte:r.End.Byte])
199	}
200


Now let me check the errors file to see if ErrSemantic exists:


List cmd package files


.rw-r--r-- steve.briggs staff  704 B  Tue May 12 21:18:58 2026 root_test.go
.rw-r--r-- steve.briggs staff  683 B  Tue May 12 23:04:26 2026 errors_test.go
.rw-r--r-- steve.briggs staff  1.5 KB Tue May 12 23:04:38 2026 errors.go
drwxr-xr-x steve.briggs staff  288 B  Tue May 12 23:12:50 2026 ..
.rw-r--r-- steve.briggs staff  3.1 KB Tue May 12 23:48:33 2026 diff_test.go
.rw-r--r-- steve.briggs staff 1005 B  Tue May 12 23:53:00 2026 versions_test.go
.rw-r--r-- steve.briggs staff  789 B  Tue May 12 23:53:11 2026 versions.go
.rw-r--r-- steve.briggs staff  1.5 KB Tue May 12 23:53:15 2026 root.go
.rw-r--r-- steve.briggs staff  5.6 KB Wed May 13 00:17:00 2026 diff.go
drwxr-xr-x steve.briggs staff  320 B  Wed May 13 00:17:00 2026 .


1	package cmd
2
3	import (
4		"context"
5		"errors"
6
7		"github.com/immuta/operations/services/crow/pkg/client"
8	)
9
10	// Sentinel errors mapped to exit codes. Packages that want a specific exit
11	// behaviour wrap these (e.g. `fmt.Errorf("extract: %w", ErrArchive)`).
12	var (
13		// ErrUsage indicates a CLI usage error (bad args, malformed module
14		// address, missing TTY for interactive mode). Maps to exit code 1.
15		ErrUsage = errors.New("usage error")
16
17		// ErrArchive indicates the fetched module tarball was corrupt or
18		// contained unsafe paths. Maps to exit code 4.
19		ErrArchive = errors.New("archive corrupt or unsafe")
20
21		// ErrSemantic indicates a parse or validation error during semantic
22		// (HCL-aware) diffing. Maps to exit code 5.
23		ErrSemantic = errors.New("semantic diff parse error")
24	)
25
26	const (
27		exitOK            = 0
28		exitUsage         = 1
29		exitNotFound      = 2
30		exitGeneric       = 3
31		exitArchive       = 4
32		exitSemantic      = 5
33		exitUserCancelled = 130
34	)
35
36	// ExitCode maps an error to a process exit code per the spec table.
37	// Returns 0 for nil.
38	func ExitCode(err error) int {
39		switch {
40		case err == nil:
41			return exitOK
42		case errors.Is(err, ErrUsage):
43			return exitUsage
44		case errors.Is(err, client.ErrNotFound):
45			return exitNotFound
46		case errors.Is(err, ErrArchive):
47			return exitArchive
48		case errors.Is(err, ErrSemantic):
49			return exitSemantic
50		case errors.Is(err, context.Canceled), errors.Is(err, context.DeadlineExceeded):
51			return exitUserCancelled
52		default:
53			return exitGeneric
54		}
55	}
56


I have all the context I need. Now let me execute the steps:

**Step 1: Add the failing test**


Edit

func TestDiffBadModuleAddress(t *testing.T) {
	root := NewRootCmd()
	var stderr bytes.Buffer
	root.SetErr(&stderr)
	root.SetArgs([]string{"diff", "bad-address", "1.0.0", "1.1.0"})
	err := root.ExecuteContext(context.Background())
	if err == nil {
		t.Fatal("expected error for bad address")
	}
	if ExitCode(err) != 1 {
		t.Errorf("exit code = %d, want 1", ExitCode(err))
	}
}

func TestDiffBadModuleAddress(t *testing.T) {
	root := NewRootCmd()
	var stderr bytes.Buffer
	root.SetErr(&stderr)
	root.SetArgs([]string{"diff", "bad-address", "1.0.0", "1.1.0"})
	err := root.ExecuteContext(context.Background())
	if err == nil {
		t.Fatal("expected error for bad address")
	}
	if ExitCode(err) != 1 {
		t.Errorf("exit code = %d, want 1", ExitCode(err))
	}
}

func TestDiffSemanticIncluded(t *testing.T) {
	srv := fakeCrowTwoVersions(t)
	root := NewRootCmd()
	var stdout bytes.Buffer
	root.SetOut(&stdout)
	root.SetArgs([]string{
		"diff",
		"iac/comply/aws", "1.0.0", "1.1.0",
		"--crow-url", srv.URL,
		"--plain",
		"--semantic",
		"--cache-dir", t.TempDir(),
	})
	if err := root.ExecuteContext(context.Background()); err != nil {
		t.Fatalf("execute: %v", err)
	}
	out := stdout.String()
	for _, want := range []string{
		"=== semantic changes ===",
		"resource",
		"aws_s3_bucket.alpha",
		"aws_s3_bucket.beta",
		"variable",
		"name",
	} {
		if !strings.Contains(out, want) {
			t.Errorf("semantic output missing %q\n--- output ---\n%s", want, out)
		}
	}
}


The file /Users/steve.briggs/projects/operations/.claude/worktrees/birdseye/apps/birdseye/cmd/diff_test.go has been updated successfully. (file state is current in your context — no need to Read it back)


**Step 2: Run to confirm failure**


Bash

cd /Users/steve.briggs/projects/operations/.claude/worktrees/birdseye/apps/birdseye && go test ./cmd/... -run TestDiffSemantic -v 2>&1

Run semantic test to confirm failure


Error: Exit code 1
=== RUN   TestDiffSemanticIncluded
    diff_test.go:146: semantic output missing "=== semantic changes ==="
        --- output ---
        === main.tf (modified) +1 -1
        --- main.tf
        +++ main.tf
        @@ -1 +1 @@
        -resource "aws_s3_bucket" "alpha" {}
        +resource "aws_s3_bucket" "beta" {}

        === variables.tf (added) +1 -0
        +++ variables.tf
        +variable "name" { type = string }
    diff_test.go:146: semantic output missing "aws_s3_bucket.alpha"
        --- output ---
        === main.tf (modified) +1 -1
        --- main.tf
        +++ main.tf
        @@ -1 +1 @@
        -resource "aws_s3_bucket" "alpha" {}
        +resource "aws_s3_bucket" "beta" {}

        === variables.tf (added) +1 -0
        +++ variables.tf
        +variable "name" { type = string }
    diff_test.go:146: semantic output missing "aws_s3_bucket.beta"
        --- output ---
        === main.tf (modified) +1 -1
        --- main.tf
        +++ main.tf
        @@ -1 +1 @@
        -resource "aws_s3_bucket" "alpha" {}
        +resource "aws_s3_bucket" "beta" {}

        === variables.tf (added) +1 -0
        +++ variables.tf
        +variable "name" { type = string }
--- FAIL: TestDiffSemanticIncluded (0.00s)
FAIL
FAIL	github.com/immuta/operations/apps/birdseye/cmd	0.619s
FAIL


Good, confirmed failing as expected. **Step 3: Update `runDiff`**


Edit

	result := diff.Result{Files: diff.Textual(modAExtracted, modBExtracted)}
	// Semantic mode wired in Task 17.

	if !o.Plain && isTTY(cmd.OutOrStdout()) {

	result := diff.Result{Files: diff.Textual(modAExtracted, modBExtracted)}
	if o.Semantic {
		sem, err := diff.Semantic(modAExtracted, modBExtracted)
		if err != nil {
			return fmt.Errorf("%w: %v", ErrSemantic, err)
		}
		result.Semantic = sem
	}

	if !o.Plain && isTTY(cmd.OutOrStdout()) {


The file /Users/steve.briggs/projects/operations/.claude/worktrees/birdseye/apps/birdseye/cmd/diff.go has been updated successfully. (file state is current in your context — no need to Read it back)


**Step 4: Replace `renderPlain` body**


func renderPlain(w io.Writer, r diff.Result) error {
	if len(r.Files) == 0 {
		_, err := fmt.Fprintln(w, "no differences")
		return err
	}
	for i, fd := range r.Files {
		if i > 0 {
			_, _ = fmt.Fprintln(w)
		}
		_, _ = fmt.Fprintf(w, "=== %s (%s) +%d -%d\n", fd.Path, fd.Status, fd.Adds, fd.Dels)
		_, _ = fmt.Fprint(w, fd.Unified)
	}
	return nil
}

func renderPlain(w io.Writer, r diff.Result) error {
	if len(r.Files) == 0 && len(r.Semantic) == 0 {
		_, err := fmt.Fprintln(w, "no differences")
		return err
	}
	for i, fd := range r.Files {
		if i > 0 {
			_, _ = fmt.Fprintln(w)
		}
		_, _ = fmt.Fprintf(w, "=== %s (%s) +%d -%d\n", fd.Path, fd.Status, fd.Adds, fd.Dels)
		_, _ = fmt.Fprint(w, fd.Unified)
	}
	if len(r.Semantic) > 0 {
		_, _ = fmt.Fprintln(w)
		_, _ = fmt.Fprintln(w, "=== semantic changes ===")
		for _, c := range r.Semantic {
			_, _ = fmt.Fprintf(w, "%s %s %s\n", c.Status, c.Kind, c.Name)
		}
	}
	return nil
}


**Step 5: Run all tests with race detector**


Bash

cd /Users/steve.briggs/projects/operations/.claude/worktrees/birdseye/apps/birdseye && go test -race ./... -v 2>&1

Run all tests with race detector


?   	github.com/immuta/operations/apps/birdseye	[no test files]
=== RUN   TestDiffPlainOutput
--- PASS: TestDiffPlainOutput (0.01s)
=== RUN   TestDiffIdenticalVersionsNoChanges
--- PASS: TestDiffIdenticalVersionsNoChanges (0.01s)
=== RUN   TestDiffBadModuleAddress
--- PASS: TestDiffBadModuleAddress (0.00s)
=== RUN   TestDiffSemanticIncluded
--- PASS: TestDiffSemanticIncluded (0.01s)
=== RUN   TestExitCode
=== RUN   TestExitCode/nil
=== RUN   TestExitCode/not-found
=== RUN   TestExitCode/wrapped-not-found
=== RUN   TestExitCode/context-cancelled
=== RUN   TestExitCode/context-deadline
=== RUN   TestExitCode/generic
--- PASS: TestExitCode (0.00s)
    --- PASS: TestExitCode/nil (0.00s)
    --- PASS: TestExitCode/not-found (0.00s)
    --- PASS: TestExitCode/wrapped-not-found (0.00s)
    --- PASS: TestExitCode/context-cancelled (0.00s)
    --- PASS: TestExitCode/context-deadline (0.00s)
    --- PASS: TestExitCode/generic (0.00s)
=== RUN   TestNewRootCmdHelp
--- PASS: TestNewRootCmdHelp (0.00s)
=== RUN   TestNewRootCmdDefaults
--- PASS: TestNewRootCmdDefaults (0.00s)
=== RUN   TestVersionsCmd
--- PASS: TestVersionsCmd (0.00s)
PASS
ok  	github.com/immuta/operations/apps/birdseye/cmd	1.831s
=== RUN   TestExtractHappyPath
--- PASS: TestExtractHappyPath (0.00s)
=== RUN   TestExtractEmptyArchive
--- PASS: TestExtractEmptyArchive (0.00s)
=== RUN   TestExtractMalformedGzip
--- PASS: TestExtractMalformedGzip (0.00s)
=== RUN   TestExtractZipSlip
=== RUN   TestExtractZipSlip/../evil.tf
=== RUN   TestExtractZipSlip/./../../etc/passwd
=== RUN   TestExtractZipSlip/a/../../etc/passwd
--- PASS: TestExtractZipSlip (0.00s)
    --- PASS: TestExtractZipSlip/../evil.tf (0.00s)
    --- PASS: TestExtractZipSlip/./../../etc/passwd (0.00s)
    --- PASS: TestExtractZipSlip/a/../../etc/passwd (0.00s)
=== RUN   TestExtractAbsolutePath
--- PASS: TestExtractAbsolutePath (0.00s)
=== RUN   TestExtractTooLarge
--- PASS: TestExtractTooLarge (0.00s)
=== RUN   TestExtractIgnoresSymlinks
--- PASS: TestExtractIgnoresSymlinks (0.00s)
PASS
ok  	github.com/immuta/operations/apps/birdseye/internal/archive	(cached)
=== RUN   TestSemanticAddedResource
--- PASS: TestSemanticAddedResource (0.00s)
=== RUN   TestSemanticRemovedVariable
--- PASS: TestSemanticRemovedVariable (0.00s)
=== RUN   TestSemanticModifiedResource
--- PASS: TestSemanticModifiedResource (0.00s)
=== RUN   TestSemanticParseError
--- PASS: TestSemanticParseError (0.00s)
=== RUN   TestTextualAdded
--- PASS: TestTextualAdded (0.00s)
=== RUN   TestTextualRemoved
--- PASS: TestTextualRemoved (0.00s)
=== RUN   TestTextualModified
--- PASS: TestTextualModified (0.00s)
=== RUN   TestTextualIdenticalReturnsEmpty
--- PASS: TestTextualIdenticalReturnsEmpty (0.00s)
=== RUN   TestTextualSortedByPath
--- PASS: TestTextualSortedByPath (0.00s)
PASS
ok  	github.com/immuta/operations/apps/birdseye/internal/diff	(cached)
=== RUN   TestMemCacheRoundTrip
--- PASS: TestMemCacheRoundTrip (0.00s)
=== RUN   TestDiskCacheMissThenHit
--- PASS: TestDiskCacheMissThenHit (0.00s)
=== RUN   TestDiskCacheSurvivesNewInstance
--- PASS: TestDiskCacheSurvivesNewInstance (0.00s)
=== RUN   TestRegistryFetchCacheMiss
--- PASS: TestRegistryFetchCacheMiss (0.00s)
=== RUN   TestRegistryFetchCacheHitSkipsNetwork
--- PASS: TestRegistryFetchCacheHitSkipsNetwork (0.00s)
=== RUN   TestRegistryFetchNotFound
--- PASS: TestRegistryFetchNotFound (0.00s)
=== RUN   TestRegistryFetchPair
--- PASS: TestRegistryFetchPair (0.00s)
=== RUN   TestRegistryFetchPairOneMissing
--- PASS: TestRegistryFetchPairOneMissing (0.00s)
PASS
ok  	github.com/immuta/operations/apps/birdseye/internal/registry	(cached)
=== RUN   TestNewBrowserDefaults
--- PASS: TestNewBrowserDefaults (0.00s)
=== RUN   TestBrowserViewContainsBothFiles
--- PASS: TestBrowserViewContainsBothFiles (0.00s)
=== RUN   TestBrowserMovesDownAndUp
--- PASS: TestBrowserMovesDownAndUp (0.00s)
=== RUN   TestBrowserQuitMessage
--- PASS: TestBrowserQuitMessage (0.00s)
=== RUN   TestBrowserJKDoesNotForwardToViewport
--- PASS: TestBrowserJKDoesNotForwardToViewport (0.00s)
=== RUN   TestPickerStartsAtAskModule
--- PASS: TestPickerStartsAtAskModule (0.00s)
=== RUN   TestPickerAdvancesOnEnter
--- PASS: TestPickerAdvancesOnEnter (0.00s)
=== RUN   TestPickerRejectsBadAddressInline
--- PASS: TestPickerRejectsBadAddressInline (0.00s)
PASS
ok  	github.com/immuta/operations/apps/birdseye/internal/tui	1.314s


All tests pass. Let me also verify `go vet` and `go build`:


cd /Users/steve.briggs/projects/operations/.claude/worktrees/birdseye/apps/birdseye && go vet ./... && go build ./... 2>&1

Run go vet and go build


(Bash completed with no output)


Clean. **Step 6: Commit**


git add apps/birdseye/cmd/diff.go apps/birdseye/cmd/diff_test.go && git commit -m "$(cat <<'EOF'
feat(birdseye): --semantic flag wired into one-shot diff output

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
EOF
)"

Commit Task 17 changes


[worktree-birdseye e00763a] feat(birdseye): --semantic flag wired into one-shot diff output
 2 files changed, 46 insertions(+), 2 deletions(-)


All steps complete. Here's the summary:

---

**Status:** DONE

**Files modified:**
- `/Users/steve.briggs/projects/operations/.claude/worktrees/birdseye/apps/birdseye/cmd/diff.go` — updated `runDiff` to call `diff.Semantic` when `o.Semantic` is true and store results in `result.Semantic`; updated `renderPlain` to check both `Files` and `Semantic` for the "no differences" path and append a `=== semantic changes ===` section when semantic entries exist
- `/Users/steve.briggs/projects/operations/.claude/worktrees/birdseye/apps/birdseye/cmd/diff_test.go` — added `TestDiffSemanticIncluded`

**Test count:** 28 tests across 5 packages, all PASS, race-clean. `TestDiffIdenticalVersionsNoChanges` continues to pass (the "no differences" guard was updated to check both `Files` and `Semantic`).

**Build/vet:** `go build ./...` and `go vet ./...` both clean.

**Commit SHA:** `e00763a`

**Nothing unexpected** — the `ErrSemantic` sentinel was already defined in `errors.go`, and the `diff.Semantic` function signature matched exactly what the plan described.