Add find_files builtin, use it to fix find_and_copy implementation

The macro find-and-copy finds all the files in the given source tree that
match the given filename patten and create <source>:<dest> pair with the
same relative path in the destination tree.

Bug: 193540681
Test: rbcrun build/make/tests/run.rbc
Change-Id: Ic4315ce2fab7a7791ab55dd9eed039205a1c721a

core/product_config.rbc

@@ -396,7 +396,8 @@ def _file_wildcard_exists(file_pattern):
 
 def _find_and_copy(pattern, from_dir, to_dir):
     """Return a copy list for the files matching the pattern."""
-    return ["%s/%s:%s/%s" % (from_dir, f, to_dir, f) for f in rblf_wildcard(pattern, from_dir)]
+    return ["%s/%s:%s/%s" % (
+        from_dir, f, to_dir, f) for f in rblf_find_files(from_dir, pattern, only_files=1)]
 
 def _filter_out(pattern, text):
     """Return all the words from `text' that do not match any word in `pattern'.

tests/device.rbc

@@ -45,7 +45,7 @@ def init(g, handle):
   cfg["PRODUCT_COPY_FILES"] += ["device_from:device_to"]
   _include1_init(g, handle)
   cfg["PRODUCT_PACKAGES"] += ["dev_after"]
-  cfg["PRODUCT_COPY_FILES"] += (rblf.find_and_copy("audio_platform_info*.xml", "device/google/redfin/audio", "||VENDOR-PATH-PH||/etc") +
+  cfg["PRODUCT_COPY_FILES"] += (rblf.find_and_copy("audio_platform_info*.xml", "device/google/redfin", "||VENDOR-PATH-PH||/etc") +
       ["xyz:/etc/xyz"])
   cfg["PRODUCT_COPY_FILES"] += rblf.copy_files("x.xml y.xml", "/etc")
   rblf.add_soong_config_namespace(g, "NS1")

tests/run.rbc

@@ -53,7 +53,7 @@ assert_eq(
       "PRODUCT_COPY_FILES": [
           "part_from:part_to",
           "device_from:device_to",
-          "device/google/redfin/audio/audio_platform_info_noextcodec_snd.xml:||VENDOR-PATH-PH||/etc/audio_platform_info_noextcodec_snd.xml",
+          "device/google/redfin/audio/audio_platform_info_noextcodec_snd.xml:||VENDOR-PATH-PH||/etc/audio/audio_platform_info_noextcodec_snd.xml",
           "xyz:/etc/xyz",
           "x.xml:/etc/x.xml",
           "y.xml:/etc/y.xml",

tools/rbcrun/README.md

@@ -68,6 +68,11 @@ will have the value of `rblf_cli.FOO` be `"bar"`
 
 Returns `True`  if *file* exists
 
+#### rblf_find_files(*top*, *file-pattern*, only_files = 0)
+
+Returns all the paths under *top* whose basename matches *pattern* (which is a shell's glob pattern). If *only_files* is
+not zero, only the paths to the regular files are returned. The returned paths are relative to *top*.
+
 #### rblf_wildcard(*glob*, *top* = None)
 
 Expands *glob*. If *top* is supplied, expands "*top*/*glob*", then removes

tools/rbcrun/host.go

@@ -16,6 +16,7 @@ package rbcrun
 
 import (
 	"fmt"
+	"io/fs"
 	"os"
 	"os/exec"
 	"path/filepath"
@@ -170,6 +171,46 @@ func wildcard(_ *starlark.Thread, b *starlark.Builtin, args starlark.Tuple,
 	return makeStringList(files), nil
 }
 
+// find(top, pattern, only_files = 0) returns all the paths under 'top'
+// whose basename matches 'pattern' (which is a shell's glob pattern).
+// If 'only_files' is non-zero, only the paths to the regular files are
+// returned. The returned paths are relative to 'top'.
+func find(_ *starlark.Thread, b *starlark.Builtin, args starlark.Tuple,
+	kwargs []starlark.Tuple) (starlark.Value, error) {
+	var top, pattern string
+	var onlyFiles int
+	if err := starlark.UnpackArgs(b.Name(), args, kwargs,
+		"top", &top, "pattern", &pattern, "only_files?", &onlyFiles); err != nil {
+		return starlark.None, err
+	}
+	top = filepath.Clean(top)
+	pattern = filepath.Clean(pattern)
+	// Go's filepath.Walk is slow, consider using OS's find
+	var res []string
+	err := filepath.WalkDir(top, func(path string, d fs.DirEntry, err error) error {
+		if err != nil {
+			if d != nil && d.IsDir() {
+				return fs.SkipDir
+			} else {
+				return nil
+			}
+		}
+		relPath := strings.TrimPrefix(path, top)
+		if len(relPath) > 0 && relPath[0] == os.PathSeparator {
+			relPath = relPath[1:]
+		}
+		// Do not return top-level dir
+		if len(relPath) == 0 {
+			return nil
+		}
+		if matched, err := filepath.Match(pattern, d.Name()); err == nil && matched && (onlyFiles == 0 || d.Type().IsRegular()) {
+			res = append(res, relPath)
+		}
+		return nil
+	})
+	return makeStringList(res), err
+}
+
 // shell(command) runs OS shell with given command and returns back
 // its output the same way as Make's $(shell ) function. The end-of-lines
 // ("\n" or "\r\n") are replaced with " " in the result, and the trailing
@@ -226,6 +267,8 @@ func setup(env []string) {
 		"rblf_env": structFromEnv(os.Environ()),
 		// To convert makefile's $(wildcard foo)
 		"rblf_file_exists": starlark.NewBuiltin("rblf_file_exists", fileExists),
+		// To convert find-copy-subdir and product-copy-files-by pattern
+		"rblf_find_files": starlark.NewBuiltin("rblf_find_files", find),
 		// To convert makefile's $(filter ...)/$(filter-out)
 		"rblf_regex": starlark.NewBuiltin("rblf_regex", regexMatch),
 		// To convert makefile's $(shell cmd)

tools/rbcrun/testdata/file_ops.star

@@ -9,11 +9,17 @@ def test():
     assert.true(not rblf_file_exists("no_such_file"), "the file no_such_file does not exist")
     files = rblf_wildcard("*.star")
     assert.true(myname in files, "expected %s in  %s" % (myname, files))
-    # RBCDATADIR is set by the caller to the path where this file resides
     files = rblf_wildcard("*.star", rblf_env.TEST_DATA_DIR)
     assert.true(myname in files, "expected %s in %s" % (myname, files))
     files = rblf_wildcard("*.xxx")
     assert.true(len(files) == 0, "expansion should be empty but contains %s" % files)
-
-
+    mydir = "testdata"
+    myrelname = "%s/%s" % (mydir, myname)
+    files = rblf_find_files(rblf_env.TEST_DATA_DIR + "/../", "*")
+    assert.true(mydir in files and myrelname in files, "expected %s and %s in %s" % (mydir, myrelname, files))
+    files = rblf_find_files(rblf_env.TEST_DATA_DIR + "/../", "*", only_files=1)
+    assert.true(mydir not in files, "did not expect %s in %s" % (mydir, files))
+    assert.true(myrelname in files, "expected %s  in %s" % (myrelname, files))
+    files = rblf_find_files(rblf_env.TEST_DATA_DIR + "/../", "*.star")
+    assert.true(myrelname in files, "expected %s in %s" % (myrelname, files))
 test()