v.builder: make it easier to reproduce the exact specific stages of -usecache module compilation by logging the full CLI options for each

Author: spytheman

vlib/v/builder/cc.v

@@ -612,11 +612,10 @@ fn (mut v Builder) setup_output_name() {
 		if v.pref.is_verbose {
 			println('Building ${v.pref.path} to ${v.pref.out_name} ...')
 		}
-		v.pref.cache_manager.mod_save(v.pref.path, '.description.txt', v.pref.path, '${v.pref.path:-30} @ ${v.pref.cache_manager.vopts}\n') or {
+		v.pref.cache_manager.mod_save(v.pref.path, '.output.description.txt', v.pref.path,
+			get_dsc_content('PREF.PATH: ${v.pref.path}\nVOPTS: ${v.pref.cache_manager.vopts}\n')) or {
 			panic(err)
 		}
-		// println('v.ast.imports:')
-		// println(v.ast.imports)
 	}
 	if os.is_dir(v.pref.out_name) {
 		verror('${os.quoted_path(v.pref.out_name)} is a directory')
@@ -1253,7 +1252,7 @@ fn (mut v Builder) build_thirdparty_obj_file(mod string, path string, moduleflag
 		verror(res.output)
 		return
 	}
-	v.pref.cache_manager.mod_save(mod, '.description.txt', obj_path, '${obj_path:-30} @ ${cmd}\n') or {
+	v.pref.cache_manager.mod_save(mod, '.thirdparty.description.txt', obj_path, get_dsc_content('OBJ_PATH: ${obj_path}\nCMD: ${cmd}\n')) or {
 		panic(err)
 	}
 	if v.pref.show_cc {
@@ -1330,3 +1329,10 @@ fn write_response_file(response_file string, response_file_content string) {
 fn write_response_file_error(response_file string, err IError) {
 	verror('Unable to write to C response file "${response_file}", error: ${err}')
 }
+
+fn get_dsc_content(suffix string) string {
+	vargs := os.args.join(' ')
+	vjobs := os.getenv('VJOBS')
+	vflags := os.getenv('VFLAGS')
+	return 'CLI: ${vargs}\nVFLAGS="${vflags}"\nVJOBS=${vjobs}\n${suffix}'
+}

vlib/v/vcache/vcache.v

@@ -16,11 +16,11 @@ import hash
 // │ ├── README.md <-- a short description of the folder's purpose.
 // │ ├── 0f
 // │ │   ├── 0f004f983ab9c487b0d7c1a0a73840a5.txt
-// │ │   ├── 0f599edf5e16c2756fbcdd4c865087ac.description.txt <-- build details
+// │ │   ├── 0f599edf5e16c2756fbcdd4c865087ac.output.description.txt <-- build details
 // │ │   └── 0f599edf5e16c2756fbcdd4c865087ac.vh
 // │ ├── 29
 // │ │   ├── 294717dd02a1cca5f2a0393fca2c5c22.o
-// │ │   └── 294717dd02a1cca5f2a0393fca2c5c22.description.txt <-- build details
+// │ │   └── 294717dd02a1cca5f2a0393fca2c5c22.output.description.txt <-- build details
 // │ ├── 62
 // │ │   └── 620d60d6b81fdcb3cab030a37fd86996.h
 // │ └── 76