compiler: make vgen use strings.Builder & allow parser creation from string

compiler/comptime.v

@@ -117,7 +117,7 @@ fn (p mut Parser) comp_time() {
 		// Parse the function and embed resulting C code in current function so that
 		// all variables are available.
 		pos := p.cgen.lines.len - 1
-		mut pp := p.v.new_parser('.vwebtmpl.v')
+		mut pp := p.v.new_parser_file('.vwebtmpl.v')
 		if !p.pref.is_debug {
 			os.rm('.vwebtmpl.v')
 		}
@@ -245,7 +245,7 @@ fn (p mut Parser) gen_array_str(typ Type) {
 		!p.table.type_has_method(elm_type2, 'str') {
 		p.error('cant print ${elm_type}[], unhandled print of ${elm_type}')
 	}
-	p.v.vgen_file.writeln('
+	p.v.vgen_buf.writeln('
 fn (a $typ.name) str() string {
 	mut sb := strings.new_builder(a.len * 3)
 	sb.write("[")
@@ -281,7 +281,7 @@ fn (p mut Parser) gen_struct_str(typ Type) {
 	}
 	sb.writeln("\n}'")
 	sb.writeln('}')
-	p.v.vgen_file.writeln(sb.str())
+	p.v.vgen_buf.writeln(sb.str())
 	// Need to manually add the definition to `fns` so that it stays
 	// at the top of the file.
 	// This function will get parsee by V after the main pass.

compiler/fn.v

@@ -178,7 +178,7 @@ fn (p mut Parser) fn_decl() {
 		}
 		// Don't allow modifying types from a different module
 		if !p.first_pass() && !p.builtin_mod && T.mod != p.mod &&
-			!p.fileis(vgen_file_name) { // allow .str() on builtin arrays
+			p.id != 'vgen' { // allow .str() on builtin arrays
 			println('T.mod=$T.mod')
 			println('p.mod=$p.mod')
 			p.error('cannot define new methods on non-local type `$receiver_typ`')

compiler/main.v

@@ -74,7 +74,7 @@ mut:
 	vroot      string
 	mod        string  // module being built with -lib
 	parsers    []Parser
-	vgen_file  os.File
+	vgen_buf   strings.Builder
 }
 
 struct Preferences {
@@ -213,7 +213,7 @@ fn main() {
 
 fn (v mut V) add_parser(parser Parser) {
        for p in v.parsers {
-               if p.file_path == parser.file_path {
+               if p.id == parser.id {
                        return
                }
        }
@@ -334,9 +334,10 @@ fn (v mut V) compile() {
 			// new vfmt is not ready yet
 		}
 	}
-	// Close the file with generated V code (str() methods etc) and parse it
+	// parse generated V code (str() methods etc)
-	v.vgen_file.close()
+	mut vgen_parser := v.new_parser_string_id(v.vgen_buf.str(), 'vgen')
-	mut vgen_parser := v.new_parser(vgen_file_name)
+	// free the string builder which held the generated methods
+	v.vgen_buf.free()
 	vgen_parser.parse(.main)
 	v.log('Done parsing.')
 	// Write everything
@@ -590,13 +591,13 @@ fn (v mut V) add_v_files_to_compile() {
 	}
 	// Parse builtin imports
 	for file in v.files {
-		mut p := v.new_parser(file)
+		mut p := v.new_parser_file(file)
 		p.parse(.imports)
 		//if p.pref.autofree {		p.scanner.text.free()		free(p.scanner)	}
 	}
 	// Parse user imports
 	for file in user_files {
-		mut p := v.new_parser(file)
+		mut p := v.new_parser_file(file)
 		p.parse(.imports)
 		//if p.pref.autofree {		p.scanner.text.free()		free(p.scanner)	}
 	}
@@ -615,7 +616,7 @@ fn (v mut V) add_v_files_to_compile() {
 			}
 			// Add all imports referenced by these libs
 			for file in vfiles {
-				mut p := v.new_parser(file, Pass.imports)
+				mut p := v.new_parser_file(file, Pass.imports)
 				p.parse()
 				
 	if p.pref.autofree {		p.scanner.text.free()		free(p.scanner)	}
@@ -635,7 +636,7 @@ fn (v mut V) add_v_files_to_compile() {
 		}
 		// Add all imports referenced by these libs
 		for file in vfiles {
-			mut p := v.new_parser(file)
+			mut p := v.new_parser_file(file)
 			p.parse(.imports)
 			//if p.pref.autofree {		p.scanner.text.free()		free(p.scanner)	}
 		}
@@ -737,9 +738,8 @@ fn (v &V) log(s string) {
 }
 
 fn new_v(args[]string) &V {
-	os.rm(vgen_file_name)
+	mut vgen_buf := strings.new_builder(1000)
-	vgen_file := os.open_append(vgen_file_name) or { panic(err) }
+	vgen_buf.writeln('module main\nimport strings')
-	vgen_file.writeln('module main\nimport strings')
 	
 	joined_args := args.join(' ')
 	target_os := get_arg(joined_args, 'os', '')
@@ -932,7 +932,7 @@ fn new_v(args[]string) &V {
 		vroot: vroot
 		pref: pref
 		mod: mod
-		vgen_file: vgen_file
+		vgen_buf: vgen_buf
 	}
 }
 

compiler/parser.v

@@ -7,10 +7,7 @@ module main
 import (
 	os
 	strings
-)
+	crypto.sha1
-
-const (
-	vgen_file_name = 'vgen.tmp'
 )
 
 // TODO rename to Token
@@ -24,6 +21,7 @@ struct Tok {
 }
 
 struct Parser {
+	id             string // unique id. if parsing file will be same as file_path
 	file_path      string // "/home/user/hello.v"
 	file_name      string // "hello.v"
 	file_platform  string // ".v", "_win.v", "_nix.v", "_mac.v", "_lin.v" ...
@@ -97,7 +95,22 @@ const (
 	MaxModuleDepth = 4
 )
 
-fn (v mut V) new_parser(path string) Parser {
+// new parser from string. parser id will be hash of s
+fn (v mut V) new_parser_string(text string) Parser {
+	return v.new_parser_string_id(text, sha1.hexhash(text))
+}
+
+// new parser from string. with id specified in `id`
+fn (v mut V) new_parser_string_id(text string, id string) Parser {
+	mut p := v.new_parser(new_scanner(text), id)
+	p.import_table = v.table.get_file_import_table(id)
+	p.scan_tokens()
+	v.add_parser(p)
+	return p
+}
+
+// new parser from file.
+fn (v mut V) new_parser_file(path string) Parser {
 	//println('new_parser("$path")')
 	mut path_pcguard := ''
 	mut path_platform := '.v'
@@ -109,20 +122,32 @@ fn (v mut V) new_parser(path string) Parser {
 		}		
 	}
 
-	//vgen_file := os.open_append(vgen_file_name) or { panic(err) }
+	mut p := v.new_parser(new_scanner_file(path), path)
+	p = { p|
+		file_path: path,
+		file_name: path.all_after('/'),
+		file_platform: path_platform,
+		file_pcguard: path_pcguard,
+		import_table: v.table.get_file_import_table(path),
+		is_script: (v.pref.is_script && path == v.dir)
+	}
+	v.cgen.file = path
+	p.scan_tokens()
+	//p.scanner.debug_tokens()
+	v.add_parser(p)
 
+	return p
+}
+
+fn (v mut V) new_parser(scanner &Scanner, id string) Parser {
 	mut p := Parser {
+		id: id
+		scanner: scanner
 		v: v
-		file_path: path
-		file_name: path.all_after('/')
-		file_platform: path_platform
-		file_pcguard: path_pcguard
-		scanner: new_scanner(path)
 		table: v.table
-		import_table: v.table.get_file_import_table(path)
 		cur_fn: EmptyFn
 		cgen: v.cgen
-		is_script: (v.pref.is_script && path == v.dir)
+		is_script: false
 		pref: v.pref
 		os: v.os
 		vroot: v.vroot
@@ -135,7 +160,11 @@ fn (v mut V) new_parser(path string) Parser {
 		p.scanner.should_print_line_on_error = false
 	}
 	v.cgen.line_directives = v.pref.is_debuggable
-	v.cgen.file = path
+	// v.cgen.file = path
+	return p
+}
+
+fn (p mut Parser) scan_tokens() {
 	for {
 		res := p.scanner.scan()
 		p.tokens << Tok {
@@ -148,9 +177,6 @@ fn (v mut V) new_parser(path string) Parser {
 				break
 		}
 	}
-	v.add_parser(p)
-	//p.scanner.debug_tokens()
-	return p
 }
 
 fn (p mut Parser) set_current_fn(f Fn) {
@@ -238,7 +264,7 @@ fn (p mut Parser) parse(pass Pass) {
 			p.error('module `builtin` cannot be imported')
 		}
 		// save file import table
-		p.table.file_imports[p.file_path] = p.import_table
+		p.table.file_imports[p.id] = p.import_table
 		return
 	}
 	// Go through every top level token or throw a compilation error if a non-top level token is met
@@ -3885,7 +3911,7 @@ fn (p mut Parser) check_and_register_used_imported_type(typ_name string) {
 
 fn (p mut Parser) check_unused_imports() {
 	// Don't run in the generated V file with `.str()`
-	if p.fileis(vgen_file_name) {
+	if p.id == 'vgen' {
 		return
 	}
 	mut output := ''

compiler/scanner.v

@@ -37,7 +37,8 @@ mut:
 	quote byte // which quote is used to denote current string: ' or "
 }
 
-fn new_scanner(file_path string) &Scanner {
+// new scanner from file.
+fn new_scanner_file(file_path string) &Scanner {
 	if !os.file_exists(file_path) {
 		verror("$file_path doesn't exist")
 	}
@@ -58,15 +59,21 @@ fn new_scanner(file_path string) &Scanner {
 		}
 	}
 
+	mut s := new_scanner(raw_text)
+	s.file_path = file_path
+
+	return s
+}
+
+// new scanner from string.
+fn new_scanner(text string) &Scanner {
 	return &Scanner {
-		file_path: file_path
+		text: text
-		text: raw_text
 		fmt_out: strings.new_builder(1000)
 		should_print_line_on_error: true
 	}
 }
 
-
 struct ScannerPos {
 mut:
    pos int
@@ -863,5 +870,3 @@ fn good_type_name(s string) bool {
 	}
 	return true
 }
-
-

compiler/table.v

@@ -855,14 +855,14 @@ fn (table &Table) qualify_module(mod string, file_path string) string {
 	return mod
 }
 
-fn (table &Table) get_file_import_table(file_path string) FileImportTable {
+fn (table &Table) get_file_import_table(id string) FileImportTable {
 	// if file_path.clone() in table.file_imports {
 	// 	return table.file_imports[file_path.clone()]
 	// }
 	// just get imports. memory error when recycling import table
-	mut fit := new_file_import_table(file_path)
+	mut fit := new_file_import_table(id)
-	if file_path in table.file_imports {
+	if id in table.file_imports {
-		fit.imports = table.file_imports[file_path].imports
+		fit.imports = table.file_imports[id].imports
 	}
 	return fit
 }