Code to get file/dir completion candidates for a prefix

tools/completion/files_test.go

@@ -0,0 +1,79 @@
+// License: GPLv3 Copyright: 2022, Kovid Goyal, <kovid at kovidgoyal.net>
+
+package completion
+
+import (
+	"fmt"
+	"io/fs"
+	"os"
+	"path/filepath"
+	"reflect"
+	"sort"
+	"testing"
+)
+
+func TestCompleteFiles(t *testing.T) {
+	tdir := t.TempDir()
+	cwd, _ := os.Getwd()
+	if cwd != "" {
+		defer os.Chdir(cwd)
+	}
+	os.Chdir(tdir)
+	os.Create(filepath.Join(tdir, "one.txt"))
+	os.Create(filepath.Join(tdir, "two.txt"))
+	os.Mkdir(filepath.Join(tdir, "odir"), 0700)
+	os.Create(filepath.Join(tdir, "odir", "three.txt"))
+	os.Create(filepath.Join(tdir, "odir", "four.txt"))
+
+	test_candidates := func(prefix string, expected ...string) {
+		if expected == nil {
+			expected = make([]string, 0)
+		}
+		sort.Strings(expected)
+		actual := make([]string, 0, len(expected))
+		complete_files(prefix, func(completion_candidate string, abspath string, d fs.DirEntry) error {
+			actual = append(actual, completion_candidate)
+			if _, err := os.Stat(abspath); err != nil {
+				t.Fatalf("Abspath does not exist: %#v", abspath)
+				return fmt.Errorf("abspath does not exist")
+			}
+			return nil
+		})
+		sort.Strings(actual)
+		if !reflect.DeepEqual(expected, actual) {
+			t.Fatalf("Did not get expected completion candidates for prefix: %#v\nExpected: %#v\nActual:   %#v", prefix, expected, actual)
+		}
+	}
+
+	test_abs_candidates := func(prefix string, expected ...string) {
+		e := make([]string, len(expected))
+		for i, x := range expected {
+			e[i] = filepath.Join(tdir, x)
+		}
+		test_candidates(prefix, e...)
+	}
+
+	test_cwd_prefix := func(prefix string, expected ...string) {
+		e := make([]string, len(expected))
+		for i, x := range expected {
+			e[i] = "./" + x
+		}
+		test_candidates("./"+prefix, e...)
+	}
+
+	test_cwd_prefix("", "one.txt", "two.txt", "odir", "odir/three.txt", "odir/four.txt")
+	test_cwd_prefix("t", "two.txt")
+	test_cwd_prefix("x")
+
+	test_abs_candidates(tdir, "one.txt", "two.txt", "odir", "odir/three.txt", "odir/four.txt")
+	test_abs_candidates(filepath.Join(tdir, "o"), "one.txt", "odir", "odir/three.txt", "odir/four.txt")
+
+	test_candidates("", "one.txt", "two.txt", "odir", "odir/three.txt", "odir/four.txt")
+	test_candidates("t", "two.txt")
+	test_candidates("o", "one.txt", "odir", "odir/three.txt", "odir/four.txt")
+	test_candidates("odir", "odir", "odir/three.txt", "odir/four.txt")
+	test_candidates("odir/", "odir/three.txt", "odir/four.txt")
+	test_candidates("odir/f", "odir/four.txt")
+	test_candidates("x")
+
+}