Support package driver running within test dirs (#188)

* split up methods

* tie it up

* Working on an in-repo test

* Clean things up

* version

* can't remember what I added this for

third_party/binary/BUILD

@@ -0,0 +1,18 @@
+remote_file(
+    name = "gosec_download",
+    url = ["https://github.com/securego/gosec/releases/download/v2.14.0/gosec_2.14.0_linux_amd64.tar.gz"],
+    hashes = ["226bd8825b7aed3d454446d1ec094f817f37859dded4211a5b707d0f36c5fdb7"],
+    test_only = True,
+)
+
+genrule(
+    name = "gosec",
+    srcs = [":gosec_download"],
+    tools = [CONFIG.ARCAT_TOOL],
+    outs = ["gosec"],
+    cmd = "$TOOLS x $SRCS -s v2.14.0",
+    binary = True,
+    test_only = True,
+    visibility = ["//tools/driver/..."],
+)
+

tools/driver/ChangeLog

@@ -1,3 +1,8 @@
+Version 0.3.0
+-------------
+    * Add search dir option which walks a current directory rather than querying plz.
+      Allows running within a Please test.
+
 Version 0.2.3
 -------------
     * Allow the caller not to provide any input files at all

tools/driver/VERSION

@@ -1 +1 @@
-0.2.3
+0.3.0

tools/driver/main.go

@@ -19,6 +19,7 @@ var opts = struct {
 	NoInput    bool              `short:"n" long:"no_input" description:"Assume a default config and don't try to read from stdin"`
 	WorkingDir string            `short:"w" long:"working_dir" description:"Change to this working directory before running"`
 	OutputFile string            `short:"o" long:"output_file" env:"PLZ_GOPACKAGESDRIVER_OUTPUT_FILE" description:"File to write output to (in addition to stdout)"`
+	SearchDir  string            `short:"s" long:"search_dir" env:"PLZ_GOPACKAGESDRIVER_SEARCHDIR" description:"Search this directory for modinfo files, instead of querying plz"`
 	Args       struct {
 		Files []string `positional-arg-name:"file"`
 	} `positional-args:"true"`
@@ -52,7 +53,7 @@ func main() {
 		}
 		log.Debug("Received driver request: %v", req)
 	}
-	resp, err := packages.Load(req, opts.Args.Files)
+	resp, err := load(req)
 	if err != nil {
 		log.Fatalf("Failed to load packages: %s", err)
 	}
@@ -70,3 +71,10 @@ func main() {
 		log.Fatalf("Failed to write packages: %s", err)
 	}
 }
+
+func load(req *packages.DriverRequest) (*packages.DriverResponse, error) {
+	if opts.SearchDir == "" {
+		return packages.Load(req, opts.Args.Files)
+	}
+	return packages.LoadOffline(req, opts.SearchDir, opts.Args.Files)
+}

tools/driver/packages/packages.go

@@ -7,6 +7,7 @@ import (
 	"go/build"
 	"go/types"
 	"io"
+	"io/fs"
 	"os"
 	"os/exec"
 	"path/filepath"
@@ -97,6 +98,35 @@ func Load(req *DriverRequest, files []string) (*DriverResponse, error) {
 	if err != nil {
 		return nil, err
 	}
+	return packagesToResponse(rootpath, pkgs, dirs)
+}
+
+// LoadOffline is like Load but rather than querying plz to find the file to load, it just
+// walks a file tree looking for pkg_info.json files.
+func LoadOffline(req *DriverRequest, searchDir string, files []string) (*DriverResponse, error) {
+	pkgs := []*packages.Package{}
+	if err := filepath.WalkDir(searchDir, func(path string, d fs.DirEntry, err error) error {
+		lpkgs := []*packages.Package{}
+		if err != nil || d.IsDir() || !strings.HasSuffix(path, "pkg_info.json") {
+			return err
+		} else if b, err := os.ReadFile(path); err != nil {
+			return fmt.Errorf("failed to read %s: %w", path, err)
+		} else if err := json.Unmarshal(b, &lpkgs); err != nil {
+			return fmt.Errorf("failed to decode %s: %w", path, err)
+		}
+		pkgs = append(pkgs, lpkgs...)
+		return nil
+	}); err != nil {
+		return nil, err
+	}
+	dirs := map[string]struct{}{}
+	for _, file := range files {
+		dirs[filepath.Dir(file)] = struct{}{}
+	}
+	return packagesToResponse(searchDir, pkgs, dirs)
+}
+
+func packagesToResponse(rootpath string, pkgs []*packages.Package, dirs map[string]struct{}) (*DriverResponse, error) {
 	// Build the set of root packages
 	seenRoots := map[string]struct{}{}
 	roots := []string{}
@@ -207,13 +237,18 @@ func loadPackageInfo(files []string) ([]*packages.Package, error) {
 	if err := build.Wait(); err != nil {
 		return nil, handleSubprocessErr(build, err)
 	}
-	log.Debug("Loading plz package info files...")
 	// Now we can read all the package info files from the build process' stdout.
+	return loadPackageInfoFiles(strings.Fields(strings.TrimSpace(build.Stdout.(*bytes.Buffer).String())))
+}
+
+// loadPackageInfoFiles loads the given set of package info files
+func loadPackageInfoFiles(paths []string) ([]*packages.Package, error) {
+	log.Debug("Loading plz package info files...")
 	pkgs := []*packages.Package{}
 	var lock sync.Mutex
 	var g errgroup.Group
 	g.SetLimit(8) // arbitrary limit since we're doing I/O
-	for _, file := range strings.Fields(strings.TrimSpace(build.Stdout.(*bytes.Buffer).String())) {
+	for _, file := range paths {
 		file := file
 		if !strings.HasSuffix(file, ".json") {
 			continue // Ignore all the various Go sources etc.

tools/driver/test/BUILD

@@ -0,0 +1,26 @@
+subinclude("//build_defs:go")
+
+# This is an integration test proving we can run within a test directory; without the
+# package driver running, gosec will get import errors from the package and fail.
+gentest(
+    name = "gosec_test",
+    tools = {
+        "driver": ["//tools/driver:plz-gopackagesdriver"],
+        "gosec": ["//third_party/binary:gosec"],
+    },
+    deps = [
+        "//tools/driver/packages",
+    ],
+    needs_transitive_deps = True,
+    cmd = [
+        'export PLZ_GOPACKAGESDRIVER_SEARCHDIR="$TMP_DIR"',
+        'export GOPACKAGESDRIVER="$TOOLS_DRIVER"',
+        '"$TOOLS_GOSEC" --exclude G104,G304,G307 tools/driver/packages',
+    ],
+    test_cmd = "true",
+    no_test_output = True,
+    requires = [
+        "go",
+        "go_src",
+    ],
+)