Merge pull request #3709 from jsternberg/dap-loaded-source-path

dap: properly map source paths to client side paths

dap/adapter.go

@@ -7,7 +7,6 @@ import (
 	"fmt"
 	"io"
 	"path"
-	"path/filepath"
 	"slices"
 	"strings"
 	"sync"
@@ -605,14 +604,14 @@ func (b *breakpointMap) Set(fname string, sbps []dap.SourceBreakpoint) (breakpoi
 	return breakpoints
 }
 
-func (b *breakpointMap) Intersect(ctx Context, src *pb.Source, ws string) map[digest.Digest]int {
+func (b *breakpointMap) Intersect(ctx Context, src *pb.Source) map[digest.Digest]int {
 	b.mu.Lock()
 	defer b.mu.Unlock()
 
 	digests := make(map[digest.Digest]int)
 
 	for dgst, locs := range src.Locations {
-		if id := b.intersect(ctx, src, locs, ws); id > 0 {
+		if id := b.intersect(ctx, src, locs); id > 0 {
 			digests[digest.Digest(dgst)] = id
 		}
 	}
@@ -620,7 +619,7 @@ func (b *breakpointMap) Intersect(ctx Context, src *pb.Source, ws string) map[di
 	// Mark unverified breakpoints as failed at this point since we couldn't find an area
 	// in the source where they applied.
 	for _, info := range src.Infos {
-		fname := filepath.Join(ws, info.Filename)
+		fname := info.Filename
 
 		bps := b.getByPath(fname)
 		for _, bp := range bps {
@@ -640,7 +639,7 @@ func (b *breakpointMap) Intersect(ctx Context, src *pb.Source, ws string) map[di
 	return digests
 }
 
-func (b *breakpointMap) intersect(ctx Context, src *pb.Source, locs *pb.Locations, ws string) int {
+func (b *breakpointMap) intersect(ctx Context, src *pb.Source, locs *pb.Locations) int {
 	overlaps := func(r *pb.Range, bp *dap.Breakpoint) bool {
 		if bp.Line < int(r.Start.Line) || bp.Line > int(r.End.Line) {
 			return false
@@ -661,7 +660,7 @@ func (b *breakpointMap) intersect(ctx Context, src *pb.Source, locs *pb.Location
 		r := loc.Ranges[0]
 
 		info := src.Infos[loc.SourceIndex]
-		fname := filepath.Join(ws, info.Filename)
+		fname := info.Filename
 
 		bps := b.getByPath(fname)
 		if len(bps) == 0 {

dap/adapter_test.go

@@ -187,12 +187,12 @@ func TestBreakpointMapIntersectVerified(t *testing.T) {
 	src := &pb.Source{
 		Locations: srcLocs,
 		Infos: []*pb.SourceInfo{
-			{Filename: filename},
+			{Filename: fpath},
 		},
 	}
 
 	ctx := newBreakpointTestContext(t)
-	digests := bm.Intersect(ctx, src, ws)
+	digests := bm.Intersect(ctx, src)
 	wantMatches := 0
 	for _, bc := range breakpointCases {
 		if bc.expectVerified {

dap/thread.go

@@ -2,9 +2,9 @@ package dap
 
 import (
 	"context"
-	"path"
 	"path/filepath"
 	"slices"
+	"strings"
 	"sync"
 
 	"github.com/docker/buildx/build"
@@ -31,10 +31,10 @@ type thread struct {
 	variables *variableReferences
 
 	// Inputs to the evaluate call.
-	c          gateway.Client
+	c             gateway.Client
-	ref        gateway.Reference
+	ref           gateway.Reference
-	meta       map[string][]byte
+	meta          map[string][]byte
-	sourcePath string
+	sourceInfoMap func(*pb.Source) *pb.Source
 
 	// LLB state for the evaluate call.
 	def    *llb.Definition
@@ -107,14 +107,21 @@ func (t *thread) init(ctx Context, c gateway.Client, ref gateway.Reference, meta
 	t.c = c
 	t.ref = ref
 	t.meta = meta
+	t.sourceInfoMap = func(s *pb.Source) *pb.Source {
+		s = s.CloneVT()
+		for _, sinfo := range s.Infos {
+			// Map the filename from the source info from the frontend location to the
+			// client location.
+			fname := strings.Replace(sinfo.Filename, inputs.DockerfileMappingDst, inputs.DockerfileMappingSrc, 1)
 
-	// Combine the dockerfile directory with the context path to find the
+			// Convert to an absolute path.
-	// real base path. The frontend will report the base path as the filename.
+			if abspath, err := filepath.Abs(fname); err == nil {
-	dir := path.Dir(inputs.DockerfilePath)
+				fname = abspath
-	if !path.IsAbs(dir) {
+			}
-		dir = path.Join(inputs.ContextPath, dir)
+			sinfo.Filename = fname
+		}
+		return s
 	}
-	t.sourcePath = dir
 
 	if err := t.getLLBState(ctx); err != nil {
 		return err
@@ -252,7 +259,7 @@ func (t *thread) getStackFrame(dgst digest.Digest, next *step) *frame {
 		f.setNameFromMeta(meta)
 	}
 	if loc, ok := t.def.Source.Locations[string(dgst)]; ok {
-		f.fillLocation(t.def, loc, t.sourcePath, next)
+		f.fillLocation(t.def, loc, next)
 	}
 	t.frames[int32(f.Id)] = f
 	return f
@@ -296,7 +303,6 @@ func (t *thread) reset() {
 	t.c = nil
 	t.ref = nil
 	t.meta = nil
-	t.sourcePath = ""
 	t.ops = nil
 }
 
@@ -462,9 +468,12 @@ func (t *thread) getLLBState(ctx Context) error {
 		return err
 	}
 
+	if t.sourceInfoMap != nil {
+		t.def.Source = t.sourceInfoMap(t.def.Source)
+	}
+
 	for _, src := range t.def.Source.Infos {
-		fname := filepath.Join(t.sourcePath, src.Filename)
+		t.sourceMap.Put(ctx, src.Filename, src.Data)
-		t.sourceMap.Put(ctx, fname, src.Data)
 	}
 
 	t.ops = make(map[digest.Digest]*pb.Op, len(t.def.Def))
@@ -483,7 +492,7 @@ func (t *thread) getLLBState(ctx Context) error {
 }
 
 func (t *thread) setBreakpoints(ctx Context) {
-	t.bps = t.breakpointMap.Intersect(ctx, t.def.Source, t.sourcePath)
+	t.bps = t.breakpointMap.Intersect(ctx, t.def.Source)
 }
 
 func (t *thread) seekNext(ctx Context, from *step, action stepType) (string, *step, map[string]gateway.Reference, error) {

dap/variables.go

@@ -38,7 +38,7 @@ func (f *frame) setNameFromMeta(meta llb.OpMetadata) {
 	// TODO: should we infer the name from somewhere else?
 }
 
-func (f *frame) fillLocation(def *llb.Definition, loc *pb.Locations, ws string, next *step) {
+func (f *frame) fillLocation(def *llb.Definition, loc *pb.Locations, next *step) {
 	for _, l := range loc.Locations {
 		for _, r := range l.Ranges {
 			if next != nil && f.Line != 0 {
@@ -57,7 +57,7 @@ func (f *frame) fillLocation(def *llb.Definition, loc *pb.Locations, ws string,
 			info := def.Source.Infos[l.SourceIndex]
 			f.Source = &dap.Source{
 				Name: path.Base(info.Filename),
-				Path: filepath.Join(ws, info.Filename),
+				Path: info.Filename,
 			}
 
 			// If we do not have a next operation, then we don't have

tests/build.go

@@ -107,7 +107,7 @@ COPY --from=base /etc/bar /bar
 `)
 	dir := tmpdir(
 		t,
-		fstest.CreateFile("foo", []byte("foo"), 0600),
+		fstest.CreateFile("foo", []byte("foo"), 0o600),
 	)
 
 	cmd := buildxCmd(sb, withDir(dir), withArgs("build", "--progress=quiet", "-f-", dir))
@@ -124,8 +124,8 @@ COPY foo /foo
 `)
 		dir := tmpdir(
 			t,
-			fstest.CreateFile("Dockerfile", dockerfile, 0600),
+			fstest.CreateFile("Dockerfile", dockerfile, 0o600),
-			fstest.CreateFile("foo", []byte("foo"), 0600),
+			fstest.CreateFile("foo", []byte("foo"), 0o600),
 		)
 		dirDest := t.TempDir()
 
@@ -149,8 +149,8 @@ COPY foo /foo
 `)
 		dir := tmpdir(
 			t,
-			fstest.CreateFile("Dockerfile", dockerfile, 0600),
+			fstest.CreateFile("Dockerfile", dockerfile, 0o600),
-			fstest.CreateFile("foo", []byte("foo"), 0600),
+			fstest.CreateFile("foo", []byte("foo"), 0o600),
 		)
 		dirDest := t.TempDir()
 
@@ -176,8 +176,8 @@ COPY foo /foo
 `)
 		dir := tmpdir(
 			t,
-			fstest.CreateFile("Dockerfile", dockerfile, 0600),
+			fstest.CreateFile("Dockerfile", dockerfile, 0o600),
-			fstest.CreateFile("foo", []byte("foo"), 0600),
+			fstest.CreateFile("foo", []byte("foo"), 0o600),
 		)
 		dirDest := t.TempDir()
 
@@ -209,8 +209,8 @@ COPY foo /foo
 `)
 		dir := tmpdir(
 			t,
-			fstest.CreateFile("Dockerfile", dockerfile, 0600),
+			fstest.CreateFile("Dockerfile", dockerfile, 0o600),
-			fstest.CreateFile("foo", []byte("foo"), 0600),
+			fstest.CreateFile("foo", []byte("foo"), 0o600),
 		)
 		dirDest := t.TempDir()
 
@@ -242,8 +242,8 @@ COPY foo /foo
 `)
 		dir := tmpdir(
 			t,
-			fstest.CreateFile("Dockerfile", dockerfile, 0600),
+			fstest.CreateFile("Dockerfile", dockerfile, 0o600),
-			fstest.CreateFile("foo", []byte("foo"), 0600),
+			fstest.CreateFile("foo", []byte("foo"), 0o600),
 		)
 		dirDest := t.TempDir()
 
@@ -275,8 +275,8 @@ COPY foo /foo
 `)
 	dir := tmpdir(
 		t,
-		fstest.CreateFile("Dockerfile", dockerfile, 0600),
+		fstest.CreateFile("Dockerfile", dockerfile, 0o600),
-		fstest.CreateFile("foo", []byte("foo"), 0600),
+		fstest.CreateFile("foo", []byte("foo"), 0o600),
 	)
 	dirDest := t.TempDir()
 
@@ -314,8 +314,8 @@ COPY --from=base /etc/bar /bar
 `)
 	dir := tmpdir(
 		t,
-		fstest.CreateFile("build.Dockerfile", dockerfile, 0600),
+		fstest.CreateFile("build.Dockerfile", dockerfile, 0o600),
-		fstest.CreateFile("foo", []byte("foo"), 0600),
+		fstest.CreateFile("foo", []byte("foo"), 0o600),
 	)
 
 	out, err := buildCmd(sb, withDir(dir), withArgs(
@@ -359,7 +359,7 @@ COPY --from=base /etc/bar /bar
 `)
 	dir := tmpdir(
 		t,
-		fstest.CreateFile("foo", []byte("foo"), 0600),
+		fstest.CreateFile("foo", []byte("foo"), 0o600),
 	)
 
 	cmd := buildxCmd(sb, withDir(dir), withArgs("build", "--progress=quiet", "--metadata-file", filepath.Join(dir, "md.json"), "-f-", dir))
@@ -397,8 +397,8 @@ COPY foo /foo
 `)
 	dir := tmpdir(
 		t,
-		fstest.CreateFile("build.Dockerfile", dockerfile, 0600),
+		fstest.CreateFile("build.Dockerfile", dockerfile, 0o600),
-		fstest.CreateFile("foo", []byte("foo"), 0600),
+		fstest.CreateFile("foo", []byte("foo"), 0o600),
 	)
 	dirDest := t.TempDir()
 
@@ -534,7 +534,7 @@ func testImageIDOutput(t *testing.T, sb integration.Sandbox) {
 	dockerfile := []byte(`FROM busybox:latest`)
 
 	dir := tmpdir(t,
-		fstest.CreateFile("Dockerfile", dockerfile, 0600),
+		fstest.CreateFile("Dockerfile", dockerfile, 0o600),
 	)
 	targetDir := t.TempDir()
 
@@ -607,7 +607,7 @@ func testBuildMobyFromLocalImage(t *testing.T, sb integration.Sandbox) {
 
 	// build image
 	dockerfile := []byte(`FROM buildx-test:busybox`)
-	dir := tmpdir(t, fstest.CreateFile("Dockerfile", dockerfile, 0600))
+	dir := tmpdir(t, fstest.CreateFile("Dockerfile", dockerfile, 0o600))
 	cmd = buildxCmd(
 		sb,
 		withArgs("build", "-q", "--output=type=cacheonly", dir),
@@ -626,7 +626,7 @@ func testBuildMobyFromLocalImage(t *testing.T, sb integration.Sandbox) {
 FROM busybox:1.35
 RUN busybox | head -1 | grep v1.36.1
 `)
-	dir = tmpdir(t, fstest.CreateFile("Dockerfile", dockerfile, 0600))
+	dir = tmpdir(t, fstest.CreateFile("Dockerfile", dockerfile, 0o600))
 	cmd = buildxCmd(
 		sb,
 		withArgs("build", "-q", "--output=type=cacheonly", dir),
@@ -642,7 +642,7 @@ func testBuildDetailsLink(t *testing.T, sb integration.Sandbox) {
 	// build simple dockerfile
 	dockerfile := []byte(`FROM busybox:latest
 RUN echo foo > /bar`)
-	dir := tmpdir(t, fstest.CreateFile("Dockerfile", dockerfile, 0600))
+	dir := tmpdir(t, fstest.CreateFile("Dockerfile", dockerfile, 0o600))
 	cmd := buildxCmd(sb, withArgs("build", "--output=type=cacheonly", dir))
 	out, err := cmd.CombinedOutput()
 	require.NoError(t, err, string(out))
@@ -652,7 +652,7 @@ RUN echo foo > /bar`)
 	home, err := os.UserHomeDir() // TODO: sandbox should create a temp home dir and expose it through its interface
 	require.NoError(t, err)
 	dbDir := path.Join(home, ".docker", "desktop-build")
-	require.NoError(t, os.MkdirAll(dbDir, 0755))
+	require.NoError(t, os.MkdirAll(dbDir, 0o755))
 	dblaFile, err := os.Create(path.Join(dbDir, ".lastaccess"))
 	require.NoError(t, err)
 	defer func() {
@@ -671,7 +671,7 @@ RUN echo foo > /bar`)
 	// build erroneous dockerfile
 	dockerfile = []byte(`FROM busybox:latest
 RUN exit 1`)
-	dir = tmpdir(t, fstest.CreateFile("Dockerfile", dockerfile, 0600))
+	dir = tmpdir(t, fstest.CreateFile("Dockerfile", dockerfile, 0o600))
 	cmd = buildxCmd(sb, withArgs("build", "--output=type=cacheonly", dir))
 	out, err = cmd.CombinedOutput()
 	require.Error(t, err, string(out))
@@ -802,8 +802,8 @@ func testBuildMultiPlatform(t *testing.T, sb integration.Sandbox) {
 	`)
 	dir := tmpdir(
 		t,
-		fstest.CreateFile("Dockerfile", dockerfile, 0600),
+		fstest.CreateFile("Dockerfile", dockerfile, 0o600),
-		fstest.CreateFile("foo", []byte("foo"), 0600),
+		fstest.CreateFile("foo", []byte("foo"), 0o600),
 	)
 	registry, err := sb.NewRegistry()
 	if errors.Is(err, integration.ErrRequirements) {
@@ -838,7 +838,7 @@ func testDockerHostGateway(t *testing.T, sb integration.Sandbox) {
 FROM busybox
 RUN ping -c 1 buildx.host-gateway-ip.local
 `)
-	dir := tmpdir(t, fstest.CreateFile("Dockerfile", dockerfile, 0600))
+	dir := tmpdir(t, fstest.CreateFile("Dockerfile", dockerfile, 0o600))
 	cmd := buildxCmd(sb, withArgs("build", "--add-host=buildx.host-gateway-ip.local:host-gateway", "--output=type=cacheonly", dir))
 	out, err := cmd.CombinedOutput()
 	if !isDockerWorker(sb) {
@@ -877,7 +877,7 @@ RUN ip a show eth0 | awk '/inet / {split($2, a, "/"); print a[1]}' > /ip-bridge.
 RUN --network=host ip a show eth0 | awk '/inet / {split($2, a, "/"); print a[1]}' > /ip-host.txt
 FROM scratch
 COPY --from=build /ip*.txt /`)
-	dir := tmpdir(t, fstest.CreateFile("Dockerfile", dockerfile, 0600))
+	dir := tmpdir(t, fstest.CreateFile("Dockerfile", dockerfile, 0o600))
 
 	cmd := buildxCmd(sb, withArgs("build", "--allow=network.host", fmt.Sprintf("--output=type=local,dest=%s", dir), dir))
 	cmd.Env = append(cmd.Env, "BUILDX_BUILDER="+builderName)
@@ -912,7 +912,7 @@ COPY --from=build /shmsize /
 	`)
 	dir := tmpdir(
 		t,
-		fstest.CreateFile("Dockerfile", dockerfile, 0600),
+		fstest.CreateFile("Dockerfile", dockerfile, 0o600),
 	)
 
 	cmd := buildxCmd(sb, withArgs("build", "--shm-size=128m", fmt.Sprintf("--output=type=local,dest=%s", dir), dir))
@@ -933,7 +933,7 @@ COPY --from=build /ulimit /
 	`)
 	dir := tmpdir(
 		t,
-		fstest.CreateFile("Dockerfile", dockerfile, 0600),
+		fstest.CreateFile("Dockerfile", dockerfile, 0o600),
 	)
 
 	cmd := buildxCmd(sb, withArgs("build", "--ulimit=nofile=1024:1024", fmt.Sprintf("--output=type=local,dest=%s", dir), dir))
@@ -1034,8 +1034,8 @@ func buildMetadataProvenanceMultiplatform(t *testing.T, sb integration.Sandbox,
 	`)
 	dir := tmpdir(
 		t,
-		fstest.CreateFile("Dockerfile", dockerfile, 0600),
+		fstest.CreateFile("Dockerfile", dockerfile, 0o600),
-		fstest.CreateFile("foo", []byte("foo"), 0600),
+		fstest.CreateFile("foo", []byte("foo"), 0o600),
 	)
 
 	registry, err := sb.NewRegistry()
@@ -1122,7 +1122,7 @@ COPy --from=base \
 	`)
 	dir := tmpdir(
 		t,
-		fstest.CreateFile("Dockerfile", dockerfile, 0600),
+		fstest.CreateFile("Dockerfile", dockerfile, 0o600),
 	)
 
 	cmd := buildxCmd(
@@ -1258,8 +1258,8 @@ COPY --from=build /token /
 	`)
 	dir := tmpdir(
 		t,
-		fstest.CreateFile("Dockerfile", dockerfile, 0600),
+		fstest.CreateFile("Dockerfile", dockerfile, 0o600),
-		fstest.CreateFile("tokenfile", []byte(token), 0600),
+		fstest.CreateFile("tokenfile", []byte(token), 0o600),
 	)
 
 	t.Run("env", func(t *testing.T) {
@@ -1347,7 +1347,7 @@ COPy --from=base \
 	`)
 		dir := tmpdir(
 			t,
-			fstest.CreateFile("Dockerfile", dockerfile, 0600),
+			fstest.CreateFile("Dockerfile", dockerfile, 0o600),
 		)
 
 		cmd := buildxCmd(sb, withArgs("build", "--call=check,format=json", dir))
@@ -1382,7 +1382,7 @@ FROM second
 	`)
 		dir := tmpdir(
 			t,
-			fstest.CreateFile("Dockerfile", dockerfile, 0600),
+			fstest.CreateFile("Dockerfile", dockerfile, 0o600),
 		)
 
 		cmd := buildxCmd(sb, withArgs("build", "--build-arg=BAR=678", "--target=target", "--call=outline,format=json", dir))
@@ -1423,7 +1423,7 @@ ARG FOO=bar
 `)
 		dir := tmpdir(
 			t,
-			fstest.CreateFile("Dockerfile", dockerfile, 0600),
+			fstest.CreateFile("Dockerfile", dockerfile, 0o600),
 		)
 
 		runOutline := func(args ...string) string {
@@ -1459,7 +1459,7 @@ FROM second AS binary
 	`)
 		dir := tmpdir(
 			t,
-			fstest.CreateFile("Dockerfile", dockerfile, 0600),
+			fstest.CreateFile("Dockerfile", dockerfile, 0o600),
 		)
 
 		cmd := buildxCmd(sb, withArgs("build", "--call=targets,format=json", dir))
@@ -1501,7 +1501,7 @@ COPy --from=base \
 	`)
 		dir := tmpdir(
 			t,
-			fstest.CreateFile("Dockerfile", dockerfile, 0600),
+			fstest.CreateFile("Dockerfile", dockerfile, 0o600),
 		)
 
 		cmd := buildxCmd(sb, withArgs("build", "--call=check,format=json", "--metadata-file", filepath.Join(dir, "md.json"), dir))
@@ -1537,7 +1537,7 @@ COPY Dockerfile .
 	`)
 		dir := tmpdir(
 			t,
-			fstest.CreateFile("Dockerfile", dockerfile, 0600),
+			fstest.CreateFile("Dockerfile", dockerfile, 0o600),
 		)
 
 		cmd := buildxCmd(sb, withArgs("build", "--call=check", dir))
@@ -1556,7 +1556,7 @@ COPY Dockerfile .
 	`)
 		dir := tmpdir(
 			t,
-			fstest.CreateFile("Dockerfile", dockerfile, 0600),
+			fstest.CreateFile("Dockerfile", dockerfile, 0o600),
 		)
 
 		cmd := buildxCmd(sb, withArgs("build", "--call=check", dir))
@@ -1575,7 +1575,7 @@ cOpy Dockerfile .
 	`)
 		dir := tmpdir(
 			t,
-			fstest.CreateFile("Dockerfile", dockerfile, 0600),
+			fstest.CreateFile("Dockerfile", dockerfile, 0o600),
 		)
 
 		cmd := buildxCmd(sb, withArgs("build", "--call=check", dir))
@@ -1594,8 +1594,8 @@ cOpy Dockerfile .
 	`)
 		dir := tmpdir(
 			t,
-			fstest.CreateDir("subdir", 0700),
+			fstest.CreateDir("subdir", 0o700),
-			fstest.CreateFile("subdir/Dockerfile", dockerfile, 0600),
+			fstest.CreateFile("subdir/Dockerfile", dockerfile, 0o600),
 		)
 		dockerfilePath := filepath.Join(dir, "subdir", "Dockerfile")
 
@@ -1618,7 +1618,7 @@ RUN cat /etc/hosts | grep myhost | grep 1.2.3.4
 RUN cat /etc/hosts | grep myhostmulti | grep 162.242.195.81
 RUN cat /etc/hosts | grep myhostmulti | grep 162.242.195.82
 `)
-	dir := tmpdir(t, fstest.CreateFile("Dockerfile", dockerfile, 0600))
+	dir := tmpdir(t, fstest.CreateFile("Dockerfile", dockerfile, 0o600))
 	cmd := buildxCmd(sb, withArgs("build",
 		"--add-host=myhost=1.2.3.4",
 		"--add-host=myhostmulti=162.242.195.81",
@@ -1649,10 +1649,9 @@ RUN cp /etc/foo /etc/bar
 FROM scratch
 COPY --from=base /etc/bar /bar
 `)
-	dir := tmpdir(
+	dir := tmpdir(t,
-		t,
+		fstest.CreateFile("Dockerfile", dockerfile, 0o600),
-		fstest.CreateFile("Dockerfile", dockerfile, 0600),
+		fstest.CreateFile("foo", []byte("foo"), 0o600),
-		fstest.CreateFile("foo", []byte("foo"), 0600),
 	)
 	return dir
 }

tests/dap_build.go

@@ -11,6 +11,7 @@ import (
 	"testing"
 	"time"
 
+	"github.com/containerd/continuity/fs/fstest"
 	"github.com/docker/buildx/commands"
 	debug "github.com/docker/buildx/dap"
 	"github.com/docker/buildx/dap/common"
@@ -78,6 +79,7 @@ var dapBuildTests = []func(t *testing.T, sb integration.Sandbox){
 	testDapBuildStopOnEntry,
 	testDapBuildSetBreakpoints,
 	testDapBuildVerifiedBreakpoints,
+	testDapBuildLoadedSource,
 	testDapBuildStepIn,
 	testDapBuildStepNext,
 	testDapBuildStepOut,
@@ -258,6 +260,103 @@ func testDapBuildVerifiedBreakpoints(t *testing.T, sb integration.Sandbox) {
 	require.ErrorAs(t, done(true), &exitErr)
 }
 
+func testDapBuildLoadedSource(t *testing.T, sb integration.Sandbox) {
+	type test struct {
+		Name           string
+		ContextPath    string
+		DockerfilePath string
+	}
+
+	runTest := func(t *testing.T, tt test, abspath bool) string {
+		dockerfile := []byte(`
+FROM busybox:latest AS base
+COPY foo /etc/foo
+RUN cp /etc/foo /etc/bar
+
+FROM scratch
+COPY --from=base /etc/bar /bar
+`)
+
+		appliers := []fstest.Applier{}
+		if tt.ContextPath != "" {
+			appliers = append(appliers, fstest.CreateDir(tt.ContextPath, 0o700))
+		}
+		if tt.DockerfilePath != "" {
+			appliers = append(appliers, fstest.CreateDir(path.Join(tt.ContextPath, tt.DockerfilePath), 0o700))
+		}
+		appliers = append(appliers,
+			fstest.CreateFile(path.Join(tt.ContextPath, tt.DockerfilePath, "Dockerfile"), dockerfile, 0o600),
+			fstest.CreateFile(path.Join(tt.ContextPath, "foo"), []byte("foo"), 0o600),
+		)
+		dir := tmpdir(t, appliers...)
+
+		client, done, err := dapBuildCmd(t, sb, withDir(dir))
+		require.NoError(t, err)
+
+		var source *dap.Source
+		client.RegisterEvent("loadedSource", func(em dap.EventMessage) {
+			e := em.(*dap.LoadedSourceEvent)
+			source = &e.Body.Source
+		})
+
+		launchCfg := commands.LaunchConfig{
+			Config: common.Config{
+				StopOnEntry: true,
+			},
+		}
+		if abspath {
+			launchCfg.ContextPath = path.Join(dir, tt.ContextPath)
+		} else {
+			launchCfg.ContextPath = tt.ContextPath
+		}
+		launchCfg.Dockerfile = path.Join(launchCfg.ContextPath, tt.DockerfilePath, "Dockerfile")
+		doLaunch(t, client, launchCfg)
+
+		interruptCh := pollInterruptEvents(client)
+		stopped := waitForInterrupt[*dap.StoppedEvent](t, interruptCh)
+		require.NotNil(t, stopped)
+
+		expected := path.Join(dir, tt.ContextPath, tt.DockerfilePath, "Dockerfile")
+		require.NotNil(t, source)
+		require.Equal(t, expected, source.Path)
+		require.Equal(t, "Dockerfile", source.Name)
+
+		var exitErr *exec.ExitError
+		require.ErrorAs(t, done(true), &exitErr)
+		return dir
+	}
+
+	for _, tt := range []test{
+		{
+			Name:        "base path",
+			ContextPath: ".",
+		},
+		{
+			Name:        "nested context",
+			ContextPath: "nested",
+		},
+		{
+			Name:           "nested dockerfile",
+			ContextPath:    ".",
+			DockerfilePath: "nested",
+		},
+		{
+			Name:           "both nested",
+			ContextPath:    "nested",
+			DockerfilePath: "subdir",
+		},
+	} {
+		t.Run(tt.Name, func(t *testing.T) {
+			t.Run("absolute paths", func(t *testing.T) {
+				runTest(t, tt, true)
+			})
+			t.Run("relative paths", func(t *testing.T) {
+				runTest(t, tt, false)
+			})
+		})
+	}
+}
+
 func testDapBuildStepIn(t *testing.T, sb integration.Sandbox) {
 	dir := createTestProject(t)
 	client, done, err := dapBuildCmd(t, sb, withArgs(dir))