markused: mark explicitly all used array and map methods with `-skip-…

…unused` (fix #21907) (#21914)

.github/workflows/linux_ci.yml

@@ -58,6 +58,8 @@ jobs:
         run: v -o v2 cmd/v && ./v2 -o v3 cmd/v && ./v3 -o v4 cmd/v
       - name: v self compilation with -skip-unused
         run: v -skip-unused -o v2 cmd/v && ./v2 -skip-unused -o v3 cmd/v && ./v3 -skip-unused -o v4 cmd/v
+      - name: Test vlib modules with -skip-unused
+        run: v -skip-unused test vlib/builtin/ vlib/math vlib/flag/ vlib/os/ vlib/strconv/
       - name: v doctor
         run: v doctor
       - name: Verify `v test` works
@@ -178,6 +180,8 @@ jobs:
       - name: V self compilation with -parallel-cc
         run: |
           v -o v2 -parallel-cc cmd/v
+      - name: Test vlib modules with -skip-unused
+        run: v -skip-unused test vlib/builtin/ vlib/math vlib/flag/ vlib/os/ vlib/strconv/
       - name: Build modules
         run: |
           v build-module vlib/os
@@ -215,6 +219,8 @@ jobs:
         #   uses: coverallsapp/[email protected]
         #   with:
         #     github-token: ${{ secrets.GITHUB_TOKEN }}
+      - name: Test vlib modules with -skip-unused
+        run: v -skip-unused test vlib/builtin/ vlib/math vlib/flag/ vlib/os/ vlib/strconv/
 
   clang:
     runs-on: ubuntu-20.04
@@ -277,6 +283,8 @@ jobs:
       - name: Build examples with -autofree
         run: |
           v -autofree -experimental -o tetris examples/tetris/tetris.v
+      - name: Test vlib modules with -skip-unused
+        run: v -skip-unused test vlib/builtin/ vlib/math vlib/flag/ vlib/os/ vlib/strconv/
       - name: Build modules
         run: |
           v build-module vlib/os

.github/workflows/macos_ci.yml

@@ -94,3 +94,5 @@ jobs:
         run: v test examples/password/
       - name: Test readline
         run: v test examples/readline/
+      - name: Test vlib modules with -skip-unused
+        run: v -skip-unused test vlib/builtin/ vlib/math vlib/flag/ vlib/os/ vlib/strconv/

.github/workflows/windows_ci.yml

@@ -75,6 +75,8 @@ jobs:
         run: v -showcc -skip-unused -prod cmd/tools/vdoctor.v
       - name: compile vup.v with -skip-unused and -prod
         run: v -showcc -skip-unused -prod cmd/tools/vup.v
+      - name: Test vlib modules with -skip-unused
+        run: v -skip-unused test vlib/builtin/ vlib/math vlib/flag/ vlib/os/ vlib/strconv/
 
   msvc:
     runs-on: windows-2019
@@ -122,6 +124,8 @@ jobs:
         run: v build-examples
       - name: v2 self compilation
         run: v -o v2.exe cmd/v && .\v2.exe -o v3.exe cmd/v
+      - name: Test vlib modules with -skip-unused
+        run: v -skip-unused test vlib/builtin/ vlib/math vlib/flag/ vlib/os/ vlib/strconv/
 
   tcc:
     runs-on: windows-2019
@@ -176,6 +180,8 @@ jobs:
         run: v -o v2.exe cmd/v && .\v2.exe -o v3.exe cmd/v && .\v3.exe -o v4.exe cmd/v
       - name: v2 self compilation with -gc boehm
         run: v -o v2.exe -gc boehm cmd/v && .\v2.exe -o v3.exe -gc boehm cmd/v && .\v3.exe -o v4.exe -gc boehm cmd/v
+      - name: Test vlib modules with -skip-unused
+        run: v -skip-unused test vlib/builtin/ vlib/math vlib/flag/ vlib/os/ vlib/strconv/
 
         ## tcc32
         # - name: Build with make.bat -tcc32

cmd/tools/vtest-all.v

@@ -111,6 +111,10 @@ fn get_all_commands() []Command {
 		okmsg: 'V can compile hello world with -skip-unused.'
 		rmfile: 'examples/hello_world'
 	}
+	res << Command{
+		line: '${vexe} -skip-unused test vlib/builtin'
+		okmsg: 'V can test vlib/builtin with -skip-unused'
+	}
 	res << Command{
 		line: '${vexe} -skip-unused -profile - examples/hello_world.v'
 		okmsg: 'V can compile hello world with both -skip-unused and -profile .'

vlib/v/markused/markused.v

@@ -52,6 +52,7 @@ pub fn mark_used(mut table ast.Table, mut pref_ pref.Preferences, ast_files []&a
 			'_option_ok',
 			'_result_ok',
 			'error',
+			'ptr_str', // TODO: remove this. It is currently needed for the auto str methods for &u8, fn types, etc; See `./v -skip-unused vlib/builtin/int_test.v`
 			// utf8_str_visible_length is used by c/str.v
 			'utf8_str_visible_length',
 			'compare_ints',

vlib/v/markused/walker.v

@@ -30,6 +30,25 @@ pub fn (mut w Walker) mark_fn_as_used(fkey string) {
 	w.used_fns[fkey] = true
 }
 
+pub fn (mut w Walker) mark_builtin_array_method_as_used(method_name string) {
+	w.mark_builtin_type_method_as_used('${ast.array_type_idx}.${method_name}', '${int(ast.array_type.ref())}.${method_name}')
+}
+
+pub fn (mut w Walker) mark_builtin_map_method_as_used(method_name string) {
+	w.mark_builtin_type_method_as_used('${ast.map_type_idx}.${method_name}', '${int(ast.map_type.ref())}.${method_name}')
+}
+
+pub fn (mut w Walker) mark_builtin_type_method_as_used(k string, rk string) {
+	if mut cfn := w.all_fns[k] {
+		w.fn_decl(mut cfn)
+	}
+	if mut cfn := w.all_fns[rk] {
+		w.fn_decl(mut cfn)
+	}
+	w.mark_fn_as_used(k)
+	w.mark_fn_as_used(rk)
+}
+
 pub fn (mut w Walker) mark_const_as_used(ckey string) {
 	$if trace_skip_unused_marked ? {
 		eprintln('    const > |${ckey}|')
@@ -516,6 +535,21 @@ pub fn (mut w Walker) call_expr(mut node ast.CallExpr) {
 	if w.used_fns[fn_name] {
 		return
 	}
+	if node.is_method {
+		if node.left_type != 0 {
+			lsym := w.table.sym(node.left_type)
+			// Note: maps and arrays are implemented in `builtin` as concrete types `map` and `array`.
+			// They are not normal generics expanded, to separate structs, parametrized on the type of the element.
+			// All []Type or map[Type]Another types are typedefs to those `map` and `array` types, and all map and array methods
+			// are actually methods on the `builtin` concrete types.
+			match lsym.kind {
+				.array { w.mark_builtin_array_method_as_used(node.name) }
+				.map { w.mark_builtin_map_method_as_used(node.name) }
+				else {}
+			}
+		}
+	}
+
 	w.mark_fn_as_used(fn_name)
 	if node.is_method && node.receiver_type.has_flag(.generic) && node.receiver_concrete_type != 0
 		&& !node.receiver_concrete_type.has_flag(.generic) {

vlib/v/tests/skip_unused/string_array_methods.run.out

@@ -0,0 +1,2 @@
+[vlib/v/tests/skip_unused/string_array_methods.vv:11] aa: ['hi', '1', '5', '3']
+[vlib/v/tests/skip_unused/string_array_methods.vv:12] bb: ['1', '3', '5', 'hi']

vlib/v/tests/skip_unused/string_array_methods.skip_unused.run.out

@@ -0,0 +1,2 @@
+[vlib/v/tests/skip_unused/string_array_methods.vv:11] aa: ['hi', '1', '5', '3']
+[vlib/v/tests/skip_unused/string_array_methods.vv:12] bb: ['1', '3', '5', 'hi']

vlib/v/tests/skip_unused/string_array_methods.vv

@@ -0,0 +1,12 @@
+aa := ['hi', '1', '5', '3']
+bb := aa.sorted_with_compare(fn (a &string, b &string) int {
+	if a < b {
+		return -1
+	}
+	if a > b {
+		return 1
+	}
+	return 0
+})
+dump(aa)
+dump(bb)