test(coverage): add unit tests across all packages; remove dead code

- Added comprehensive table-driven test suites for all packages:
  cmd/glint, cicontext, fetcher, graph, linter, model, resolver.
  Coverage reaches 98%+ statement coverage across the codebase.
- Replaced os.Exit calls in cmd/glint with an `exit` variable so tests
  can capture exit codes without terminating the test process.
- Removed unreachable code found during coverage analysis:
  dead guard in cicontext.parseRegexLiteral; dead len(jobs)==0 branch
  in graph.Pipeline; skipWin struct field and dead continue in
  graph.convertToPNG; pipelineSVG return type simplified to string.

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

internal/graph/render_test.go

@@ -0,0 +1,347 @@
+package graph
+
+import (
+	"os"
+	"strings"
+	"testing"
+
+	"git.k3nny.fr/glint/internal/model"
+)
+
+// ── svgEsc ────────────────────────────────────────────────────────────────────
+
+func TestSvgEsc(t *testing.T) {
+	cases := []struct{ in, want string }{
+		{"hello", "hello"},
+		{"a&b", "a&b"},
+		{"<tag>", "&lt;tag&gt;"},
+		{"a&b<c>d", "a&amp;b&lt;c&gt;d"},
+	}
+	for _, tc := range cases {
+		if got := svgEsc(tc.in); got != tc.want {
+			t.Errorf("svgEsc(%q)=%q want %q", tc.in, got, tc.want)
+		}
+	}
+}
+
+// ── svgTrunc ──────────────────────────────────────────────────────────────────
+
+func TestSvgTrunc(t *testing.T) {
+	cases := []struct {
+		s      string
+		maxLen int
+		want   string
+	}{
+		{"short", 20, "short"},
+		{"exactly20charslong!", 20, "exactly20charslong!"},
+		{"this-is-a-very-long-job-name", 20, "this-is-a-very-long…"},
+		{"αβγδεζηθικλμνξο", 5, "αβγδ…"},
+	}
+	for _, tc := range cases {
+		got := svgTrunc(tc.s, tc.maxLen)
+		if got != tc.want {
+			t.Errorf("svgTrunc(%q, %d)=%q want %q", tc.s, tc.maxLen, got, tc.want)
+		}
+	}
+}
+
+// ── svgEmpty ──────────────────────────────────────────────────────────────────
+
+func TestSvgEmpty(t *testing.T) {
+	out := svgEmpty()
+	if !strings.Contains(out, "<svg") { t.Error("expected <svg") }
+	if !strings.Contains(out, "no jobs defined") { t.Error("expected 'no jobs defined'") }
+}
+
+// ── chipColor ─────────────────────────────────────────────────────────────────
+
+func TestChipColor(t *testing.T) {
+	if chipColor(model.Job{Trigger: "x"}) != "#6b4fbb" { t.Error("trigger color") }
+	if chipColor(model.Job{When: "manual"}) != "#fc6d26" { t.Error("manual color") }
+	if chipColor(model.Job{When: "delayed"}) != "#fca326" { t.Error("delayed color") }
+	if chipColor(model.Job{}) != "#1f75cb" { t.Error("regular color") }
+}
+
+// ── drawChipIcon ──────────────────────────────────────────────────────────────
+
+func TestDrawChipIcon(t *testing.T) {
+	cases := []struct {
+		job     model.Job
+		wantTag string
+	}{
+		{model.Job{Trigger: "x"}, "<polyline"},
+		{model.Job{When: "manual"}, "<polygon"},
+		{model.Job{When: "delayed"}, "<circle"},
+		{model.Job{}, "<polyline"},
+	}
+	for _, tc := range cases {
+		var sb strings.Builder
+		drawChipIcon(&sb, tc.job, 10, 10)
+		if !strings.Contains(sb.String(), tc.wantTag) {
+			t.Errorf("drawChipIcon(%q): want %s, got:\n%s", tc.job.When, tc.wantTag, sb.String())
+		}
+	}
+}
+
+// ── pipelineSVG ───────────────────────────────────────────────────────────────
+
+func TestPipelineSVG_Empty(t *testing.T) {
+	svg := pipelineSVG(&model.Pipeline{})
+	if !strings.Contains(svg, "no jobs defined") {
+		t.Errorf("expected 'no jobs defined', got:\n%s", svg)
+	}
+}
+
+func TestPipelineSVG_ClassicMode(t *testing.T) {
+	p := &model.Pipeline{
+		Stages: []string{"build", "test"},
+		Jobs: map[string]model.Job{
+			"build-job": {Name: "build-job", Stage: "build"},
+			"test-job":  {Name: "test-job", Stage: "test"},
+		},
+	}
+	svg := pipelineSVG(p)
+	if !strings.Contains(svg, "<svg") { t.Error("expected <svg") }
+	if !strings.Contains(svg, "build-job") { t.Error("expected build-job") }
+	if !strings.Contains(svg, "test-job") { t.Error("expected test-job") }
+	// Classic mode connector
+	if !strings.Contains(svg, "<polyline") && !strings.Contains(svg, "<line") {
+		t.Error("expected connector in classic mode")
+	}
+}
+
+func TestPipelineSVG_DAGMode(t *testing.T) {
+	p := &model.Pipeline{
+		Stages: []string{"build", "test"},
+		Jobs: map[string]model.Job{
+			"build-job": {Name: "build-job", Stage: "build"},
+			"test-job":  {Name: "test-job", Stage: "test", Needs: []any{"build-job"}},
+		},
+	}
+	svg := pipelineSVG(p)
+	// DAG mode draws <path> bezier curves
+	if !strings.Contains(svg, "<path") {
+		t.Error("expected <path> connector in DAG mode")
+	}
+}
+
+func TestPipelineSVG_DAGMode_StraightConnector(t *testing.T) {
+	// Two stages at same height → straight <line> connector in classic mode
+	p := &model.Pipeline{
+		Stages: []string{"a", "b"},
+		Jobs: map[string]model.Job{
+			"j1": {Name: "j1", Stage: "a"},
+			"j2": {Name: "j2", Stage: "b"},
+		},
+	}
+	svg := pipelineSVG(p)
+	if !strings.Contains(svg, "<svg") { t.Error("expected <svg") }
+}
+
+func TestPipelineSVG_AllJobTypes(t *testing.T) {
+	p := &model.Pipeline{
+		Stages: []string{"deploy"},
+		Jobs: map[string]model.Job{
+			"manual-job":  {Name: "manual-job", Stage: "deploy", When: "manual"},
+			"delayed-job": {Name: "delayed-job", Stage: "deploy", When: "delayed"},
+			"trigger-job": {Name: "trigger-job", Stage: "deploy", Trigger: "other/project"},
+		},
+	}
+	svg := pipelineSVG(p)
+	// Each type has its own color in the SVG
+	if !strings.Contains(svg, "#fc6d26") { t.Error("expected manual color") }
+	if !strings.Contains(svg, "#fca326") { t.Error("expected delayed color") }
+	if !strings.Contains(svg, "#6b4fbb") { t.Error("expected trigger color") }
+}
+
+func TestPipelineSVG_JobNoStage(t *testing.T) {
+	p := &model.Pipeline{
+		Jobs: map[string]model.Job{
+			"myjob": {Name: "myjob"},
+		},
+	}
+	svg := pipelineSVG(p)
+	if !strings.Contains(svg, "myjob") { t.Error("expected myjob") }
+}
+
+func TestPipelineSVG_CrossPipelineNeed(t *testing.T) {
+	p := &model.Pipeline{
+		Stages: []string{"build"},
+		Jobs: map[string]model.Job{
+			"j": {Name: "j", Stage: "build",
+				Needs: []any{map[string]any{"pipeline": "other", "job": "x"}}},
+		},
+	}
+	svg := pipelineSVG(p)
+	if !strings.Contains(svg, "<svg") { t.Error("expected <svg") }
+}
+
+// ── RenderPipeline ────────────────────────────────────────────────────────────
+
+func TestRenderPipeline(t *testing.T) {
+	p := &model.Pipeline{
+		Stages: []string{"build"},
+		Jobs: map[string]model.Job{
+			"build-job": {Name: "build-job", Stage: "build"},
+		},
+	}
+	dir := t.TempDir()
+	path, err := RenderPipeline(p, dir)
+	if err != nil {
+		t.Fatalf("RenderPipeline: %v", err)
+	}
+	if _, statErr := os.Stat(path); statErr != nil {
+		t.Errorf("output file not found: %v", statErr)
+	}
+}
+
+func TestRenderPipeline_InvalidDir(t *testing.T) {
+	// Writing to a path under a file (not a dir) should error.
+	dir := t.TempDir()
+	filePath := dir + "/notadir"
+	if err := os.WriteFile(filePath, []byte("x"), 0o644); err != nil {
+		t.Fatal(err)
+	}
+	_, err := RenderPipeline(&model.Pipeline{}, filePath+"/nested")
+	if err == nil {
+		t.Error("expected error writing to path under a file")
+	}
+}
+
+func TestRenderPipeline_WriteFileFails(t *testing.T) {
+	if os.Getuid() == 0 {
+		t.Skip("skipping as root — file permissions don't apply")
+	}
+	dir := t.TempDir()
+	if err := os.Chmod(dir, 0o555); err != nil {
+		t.Fatal(err)
+	}
+	t.Cleanup(func() { os.Chmod(dir, 0o755) })
+
+	p := &model.Pipeline{
+		Stages: []string{"build"},
+		Jobs:   map[string]model.Job{"j": {Name: "j", Stage: "build"}},
+	}
+	_, err := RenderPipeline(p, dir)
+	if err == nil {
+		t.Error("expected error when writing SVG to read-only directory")
+	}
+}
+
+// ── convertToPNG ─────────────────────────────────────────────────────────────
+
+func TestRenderPipeline_SVGFallback(t *testing.T) {
+	// With no converters on PATH, RenderPipeline returns the SVG path (line 53).
+	origPath := os.Getenv("PATH")
+	os.Setenv("PATH", "")
+	t.Cleanup(func() { os.Setenv("PATH", origPath) })
+
+	p := &model.Pipeline{
+		Stages: []string{"build"},
+		Jobs:   map[string]model.Job{"j": {Name: "j", Stage: "build"}},
+	}
+	dir := t.TempDir()
+	path, err := RenderPipeline(p, dir)
+	if err != nil {
+		t.Fatalf("RenderPipeline: %v", err)
+	}
+	if !strings.HasSuffix(path, ".svg") {
+		t.Errorf("expected .svg output when no converter available, got %q", path)
+	}
+}
+
+func TestConvertToPNG_NoConverter(t *testing.T) {
+	// In a test environment without rsvg-convert/inkscape/magick, returns false.
+	// We can't assert false because the CI machine might have one of them,
+	// but we can assert it doesn't panic.
+	dir := t.TempDir()
+	svgPath := dir + "/test.svg"
+	pngPath := dir + "/test.png"
+	_ = os.WriteFile(svgPath, []byte(`<svg xmlns="http://www.w3.org/2000/svg"/>`), 0o644)
+	// result is either true (converter found) or false (no converter) — just no panic
+	convertToPNG(svgPath, pngPath)
+}
+
+func TestConvertToPNG_FakeConverter(t *testing.T) {
+	// Install a fake rsvg-convert that just creates the output file and exits 0.
+	// This exercises the "return true" branch (line 72) and os.Remove in RenderPipeline.
+	binDir := t.TempDir()
+	script := "#!/bin/sh\n# rsvg-convert --output <out> <in>\ncp \"$3\" \"$2\"\n"
+	fakeBin := binDir + "/rsvg-convert"
+	if err := os.WriteFile(fakeBin, []byte(script), 0o755); err != nil {
+		t.Fatal(err)
+	}
+	origPath := os.Getenv("PATH")
+	os.Setenv("PATH", binDir+":"+origPath)
+	t.Cleanup(func() { os.Setenv("PATH", origPath) })
+
+	svgDir := t.TempDir()
+	svgPath := svgDir + "/test.svg"
+	pngPath := svgDir + "/test.png"
+	if err := os.WriteFile(svgPath, []byte(`<svg xmlns="http://www.w3.org/2000/svg"/>`), 0o644); err != nil {
+		t.Fatal(err)
+	}
+	ok := convertToPNG(svgPath, pngPath)
+	if !ok {
+		t.Error("expected convertToPNG to return true with fake rsvg-convert")
+	}
+}
+
+func TestRenderPipeline_PNGConversion(t *testing.T) {
+	// Verify the PNG path is returned (and SVG removed) when converter succeeds.
+	binDir := t.TempDir()
+	script := "#!/bin/sh\ncp \"$3\" \"$2\"\n"
+	if err := os.WriteFile(binDir+"/rsvg-convert", []byte(script), 0o755); err != nil {
+		t.Fatal(err)
+	}
+	origPath := os.Getenv("PATH")
+	os.Setenv("PATH", binDir+":"+origPath)
+	t.Cleanup(func() { os.Setenv("PATH", origPath) })
+
+	p := &model.Pipeline{
+		Stages: []string{"build"},
+		Jobs:   map[string]model.Job{"j": {Name: "j", Stage: "build"}},
+	}
+	dir := t.TempDir()
+	path, err := RenderPipeline(p, dir)
+	if err != nil {
+		t.Fatalf("RenderPipeline: %v", err)
+	}
+	if !strings.HasSuffix(path, ".png") {
+		t.Errorf("expected .png output, got %q", path)
+	}
+}
+
+// ── pipelineSVG coverage gaps ─────────────────────────────────────────────────
+
+func TestPipelineSVG_LShapedElbow(t *testing.T) {
+	// Classic mode with unequal stage sizes → different column heights → L-shaped elbow
+	p := &model.Pipeline{
+		Stages: []string{"build", "test"},
+		Jobs: map[string]model.Job{
+			"j1": {Name: "j1", Stage: "build"},
+			"j2": {Name: "j2", Stage: "test"},
+			"j3": {Name: "j3", Stage: "test"},
+		},
+	}
+	svg := pipelineSVG(p)
+	if !strings.Contains(svg, "<polyline") {
+		t.Error("expected <polyline> for L-shaped elbow connector")
+	}
+}
+
+func TestPipelineSVG_DAGNeedNotInPositionMap(t *testing.T) {
+	// DAG mode: job needs a template job (starts with .) → dep not in position maps → continue
+	p := &model.Pipeline{
+		Stages: []string{"build"},
+		Jobs: map[string]model.Job{
+			"j": {Name: "j", Stage: "build", Needs: []any{".hidden-template"}},
+			".hidden-template": {Name: ".hidden-template", Stage: "build"},
+		},
+	}
+	svg := pipelineSVG(p)
+	// Should render without panic; .hidden-template is not visible so no connector drawn.
+	if !strings.Contains(svg, "<svg") {
+		t.Error("expected valid SVG output")
+	}
+}