tools: make v watch webserver.v monitor files used through $tmpl as well

cmd/tools/vwatch.v

@@ -112,8 +112,8 @@ fn (mut context Context) get_stats_for_affected_vfiles() []VFileStat {
 		// The next command will make V parse the program, and print all .v files,
 		// needed for its compilation, without actually compiling it.
 		copts := context.opts.join(' ')
-		cmd := '"${context.vexe}" -silent -print-v-files ${copts}'
-		// context.elog('> cmd: $cmd')
+		cmd := '"${context.vexe}" -silent -print-watched-files ${copts}'
+		// context.elog('> cmd: ${cmd}')
 		mut paths := []string{}
 		if context.add_files.len > 0 && context.add_files[0] != '' {
 			paths << context.add_files
@@ -121,7 +121,11 @@ fn (mut context Context) get_stats_for_affected_vfiles() []VFileStat {
 		vfiles := os.execute(cmd)
 		if vfiles.exit_code == 0 {
 			paths_trimmed := vfiles.output.trim_space()
-			paths << paths_trimmed.split('\n')
+			reported_used_files := paths_trimmed.split('\n')
+			$if trace_reported_used_files ? {
+				context.elog('reported_used_files: ${reported_used_files}')
+			}
+			paths << reported_used_files
 		}
 		for vf in paths {
 			apaths[os.real_path(os.dir(vf))] = true

vlib/v/ast/ast.v

@@ -771,6 +771,7 @@ pub mut:
 	notices          []errors.Notice   // all the checker notices in the file
 	generic_fns      []&FnDecl
 	global_labels    []string // from `asm { .globl labelname }`
+	template_paths   []string // all the .html/.md files that were processed with $tmpl
 }
 
 [unsafe]

vlib/v/builder/builder.v

@@ -243,6 +243,15 @@ pub fn (mut b Builder) parse_imports() {
 		}
 		exit(0)
 	}
+	if b.pref.print_watched_files {
+		for p in b.parsed_files {
+			println(p.path)
+			for tp in p.template_paths {
+				println(tp)
+			}
+		}
+		exit(0)
+	}
 	if b.pref.dump_files != '' {
 		b.dump_files(b.parsed_files.map(it.path))
 	}

vlib/v/parser/parser.v

@@ -103,6 +103,7 @@ pub mut:
 	warnings       []errors.Warning
 	notices        []errors.Notice
 	vet_errors     []vet.Error
+	template_paths []string // record all compiled $tmpl files; needed for `v watch run webserver.v`
 }
 
 __global codegen_files = unsafe { []&ast.File{} }
@@ -372,6 +373,7 @@ pub fn (mut p Parser) parse() &ast.File {
 		warnings: warnings
 		notices: notices
 		global_labels: p.global_labels
+		template_paths: p.template_paths
 	}
 }
 

vlib/v/parser/tmpl.v

@@ -97,6 +97,7 @@ pub fn (mut p Parser) compile_template_file(template_file string, fn_name string
 		p.error('reading from ${template_file} failed')
 		return ''
 	}
+	p.template_paths << template_file
 	basepath := os.dir(template_file)
 	lstartlength := lines.len * 30
 	tmpl_str_start := "\tsb_${fn_name}.write_string('"
@@ -195,6 +196,7 @@ fn vweb_tmpl_${fn_name}() string {
 				})
 				''
 			}
+			p.template_paths << file_path
 			file_splitted := file_content.split_into_lines().reverse()
 			for f in file_splitted {
 				tline_number--

vlib/v/pref/pref.v

@@ -195,7 +195,10 @@ pub mut:
 	//
 	run_args     []string // `v run x.v 1 2 3` => `1 2 3`
 	printfn_list []string // a list of generated function names, whose source should be shown, for debugging
+	//
 	print_v_files       bool // when true, just print the list of all parsed .v files then stop.
+	print_watched_files bool // when true, just print the list of all parsed .v files + all the compiled $tmpl files, then stop. Used by `v watch run webserver.v`
+	//
 	skip_running     bool // when true, do no try to run the produced file (set by b.cc(), when -o x.c or -o x.js)
 	skip_warnings    bool // like C's "-w", forces warnings to be ignored.
 	warn_impure_v    bool // -Wimpure-v, force a warning for JS.fn()/C.fn(), outside of .js.v/.c.v files. TODO: turn to an error by default
@@ -662,6 +665,9 @@ pub fn parse_args_and_show_errors(known_external_commands []string, args []strin
 			'-print-v-files' {
 				res.print_v_files = true
 			}
+			'-print-watched-files' {
+				res.print_watched_files = true
+			}
 			'-os' {
 				target_os := cmdline.option(current_args, '-os', '')
 				i++