From 81b44dc2c96d20bdc7ebe69438d68b1cb84503fd Mon Sep 17 00:00:00 2001
From: Alexander Medvednikov <alexander@medvednikov.com>
Date: Fri, 29 May 2020 04:30:00 +0200
Subject: [PATCH] generics: generic call inside generic call; checker: check
 mut args at call

---
 examples/vweb/vweb_example.v |  2 +-
 vlib/sync/pool.v             |  2 +-
 vlib/v/checker/checker.v     | 14 +++++++++++++
 vlib/v/gen/cgen.v            | 38 +++++++++++++++---------------------
 vlib/v/gen/fn.v              |  7 +++++++
 vlib/v/parser/fn.v           | 10 ++++++++--
 vlib/v/table/table.v         |  2 +-
 vlib/v/tests/generics_test.v |  2 +-
 vlib/vweb/vweb.v             |  2 +-
 9 files changed, 50 insertions(+), 29 deletions(-)

diff --git a/examples/vweb/vweb_example.v b/examples/vweb/vweb_example.v
index 9bbdd0ee15..6fea04f88b 100644
--- a/examples/vweb/vweb_example.v
+++ b/examples/vweb/vweb_example.v
@@ -17,7 +17,7 @@ fn main() {
 	vweb.run<App>(port)
 }
 
-pub fn (mut app App) init() {
+pub fn (app App) init() {
 	app.vweb.handle_static('.')
 }
 
diff --git a/vlib/sync/pool.v b/vlib/sync/pool.v
index 8cbaf79b13..52ed9b08e9 100644
--- a/vlib/sync/pool.v
+++ b/vlib/sync/pool.v
@@ -116,7 +116,7 @@ pub fn (mut pool PoolProcessor) work_on_pointers(items []voidptr) {
 	pool.thread_contexts << [voidptr(0)].repeat(pool.items.len)
 	pool.waitgroup.add(njobs)
 	for i := 0; i < njobs; i++ {
-		go process_in_thread(pool,i)
+		go process_in_thread(mut pool,i)
 	}
 	pool.waitgroup.wait()
 }
diff --git a/vlib/v/checker/checker.v b/vlib/v/checker/checker.v
index 0d3a2077de..8caa823346 100644
--- a/vlib/v/checker/checker.v
+++ b/vlib/v/checker/checker.v
@@ -860,6 +860,16 @@ pub fn (mut c Checker) call_fn(mut call_expr ast.CallExpr) table.Type {
 		// TODO: impl typeof properly (probably not going to be a fn call)
 		return table.string_type
 	}
+	if call_expr.generic_type == table.t_type {
+		if c.mod != '' && c.mod != 'main' {
+			// Need to prepend the module when adding a generic type to a function
+			// `fn_gen_types['mymod.myfn'] == ['string', 'int']`
+			c.table.register_fn_gen_type(c.mod + '.' + fn_name, c.cur_generic_type)
+		} else {
+			c.table.register_fn_gen_type(fn_name, c.cur_generic_type)
+		}
+		// call_expr.generic_type = c.unwrap_generic(call_expr.generic_type)
+	}
 	// if c.fileis('json_test.v') {
 	// println(fn_name)
 	// }
@@ -984,6 +994,10 @@ pub fn (mut c Checker) call_fn(mut call_expr ast.CallExpr) table.Type {
 		if f.is_variadic && typ.flag_is(.variadic) && call_expr.args.len - 1 > i {
 			c.error('when forwarding a varg variable, it must be the final argument', call_expr.pos)
 		}
+		if arg.is_mut && !call_arg.is_mut {
+			c.error('`$arg.name` is a mutable argument, you need to provide `mut`: `${call_expr.name}(mut ...)`',
+				call_arg.expr.position())
+		}
 		// Handle expected interface
 		if arg_typ_sym.kind == .interface_ {
 			c.type_implements(typ, arg.typ, call_arg.expr.position())
diff --git a/vlib/v/gen/cgen.v b/vlib/v/gen/cgen.v
index ca6a4b31b5..fcf8f36c17 100644
--- a/vlib/v/gen/cgen.v
+++ b/vlib/v/gen/cgen.v
@@ -384,8 +384,10 @@ typedef struct {
 			.alias {
 				parent := &g.table.types[typ.parent_idx]
 				styp := typ.name.replace('.', '__')
-				is_c_parent := parent.name.len > 2 && parent.name[0] == `C` && parent.name[1] == `.`
-				parent_styp := if is_c_parent { 'struct ' + parent.name[2..].replace('.', '__') } else { parent.name.replace('.', '__') }
+				is_c_parent := parent.name.len > 2 && parent.name[0] == `C` && parent.name[1] ==
+					`.`
+				parent_styp := if is_c_parent { 'struct ' + parent.name[2..].replace('.', '__') } else { parent.name.replace('.',
+						'__') }
 				g.definitions.writeln('typedef $parent_styp $styp;')
 			}
 			.array {
@@ -842,7 +844,9 @@ fn (mut g Gen) expr_with_cast(expr ast.Expr, got_type, expected_type table.Type)
 	got_is_ptr := got_type.is_ptr()
 	expected_is_ptr := expected_type.is_ptr()
 	neither_void := table.voidptr_type !in [got_type, expected_type]
-	if got_is_ptr && !expected_is_ptr && neither_void && expected_sym.kind !in [.interface_, .placeholder] {
+	if got_is_ptr && !expected_is_ptr && neither_void && expected_sym.kind !in [.interface_,
+		.placeholder
+	] {
 		got_deref_type := got_type.deref()
 		deref_sym := g.table.get_type_symbol(got_deref_type)
 		deref_will_match := expected_type in [got_type, got_deref_type, deref_sym.parent_idx]
@@ -901,7 +905,8 @@ fn (mut g Gen) gen_assign_stmt(assign_stmt ast.AssignStmt) {
 	if return_type != table.void_type && return_type != 0 {
 		sym := g.table.get_type_symbol(return_type)
 		// the left vs. right is ugly and should be removed
-		if sym.kind == .multi_return || assign_stmt.left.len > assign_stmt.right.len || assign_stmt.left.len > 1 {
+		if sym.kind == .multi_return || assign_stmt.left.len > assign_stmt.right.len || assign_stmt.left.len >
+			1 {
 			// multi return
 			// TODO Handle in if_expr
 			is_optional := return_type.flag_is(.optional)
@@ -1317,6 +1322,9 @@ fn (mut g Gen) expr(node ast.Expr) {
 		ast.CharLiteral {
 			g.write("'$it.val'")
 		}
+		ast.ComptimeCall {
+			g.write('/*c*/')
+		}
 		ast.ConcatExpr {
 			g.concat_expr(it)
 		}
@@ -1836,7 +1844,8 @@ fn (mut g Gen) match_expr(node ast.MatchExpr) {
 		g.writeln('// match 0')
 		return
 	}
-	is_expr := (node.is_expr && node.return_type != table.void_type) || g.inside_ternary > 0
+	is_expr := (node.is_expr && node.return_type != table.void_type) || g.inside_ternary >
+		0
 	if is_expr {
 		g.inside_ternary++
 		// g.write('/* EM ret type=${g.typ(node.return_type)}		expected_type=${g.typ(node.expected_type)}  */')
@@ -2202,14 +2211,9 @@ fn (mut g Gen) index_expr(node ast.IndexExpr) {
 [inline]
 fn (g Gen) expr_is_multi_return_call(expr ast.Expr) bool {
 	match expr {
-		ast.CallExpr {
-			return g.table.get_type_symbol(it.return_type).kind == .multi_return
-		}
-		else {
-			return false
-		}
+		ast.CallExpr { return g.table.get_type_symbol(it.return_type).kind == .multi_return }
+		else { return false }
 	}
-
 }
 
 fn (mut g Gen) return_statement(node ast.Return) {
@@ -2247,20 +2251,15 @@ fn (mut g Gen) return_statement(node ast.Return) {
 		} else {
 			styp = g.typ(g.fn_decl.return_type)
 		}
-
 		// Use this to keep the tmp assignments in order
 		mut multi_unpack := ''
-
-
 		g.write('($styp){')
-
 		mut arg_idx := 0
 		for i, expr in node.exprs {
 			// Check if we are dealing with a multi return and handle it seperately
 			if g.expr_is_multi_return_call(expr) {
 				c := expr as ast.CallExpr
 				expr_sym := g.table.get_type_symbol(c.return_type)
-
 				// Create a tmp for this call
 				tmp := g.new_tmp_var()
 				s := g.go_before_stmt(0)
@@ -2270,7 +2269,6 @@ fn (mut g Gen) return_statement(node ast.Return) {
 				g.writeln(';')
 				multi_unpack += g.go_before_stmt(0)
 				g.write(s)
-
 				expr_types := expr_sym.mr_info().types
 				for j, _ in expr_types {
 					g.write('.arg$arg_idx=${tmp}.arg$j')
@@ -2279,10 +2277,8 @@ fn (mut g Gen) return_statement(node ast.Return) {
 					}
 					arg_idx++
 				}
-
 				continue
 			}
-
 			g.write('.arg$arg_idx=')
 			g.expr(expr)
 			arg_idx++
@@ -2291,11 +2287,9 @@ fn (mut g Gen) return_statement(node ast.Return) {
 			}
 		}
 		g.write('}')
-
 		if fn_return_is_optional {
 			g.write(' }, sizeof($styp))')
 		}
-
 		// Make sure to add our unpacks
 		g.insert_before_stmt(multi_unpack)
 	} else if node.exprs.len >= 1 {
diff --git a/vlib/v/gen/fn.v b/vlib/v/gen/fn.v
index 47512ccca4..4c43023ff2 100644
--- a/vlib/v/gen/fn.v
+++ b/vlib/v/gen/fn.v
@@ -12,6 +12,9 @@ fn (mut g Gen) gen_fn_decl(it ast.FnDecl) {
 		// || it.no_body {
 		return
 	}
+	//if g.fileis('vweb.v') {
+		//println('\ngen_fn_decl() $it.name $it.is_generic $g.cur_generic_type')
+	//}
 	former_cur_fn := g.cur_fn
 	g.cur_fn = &it
 	defer {
@@ -760,3 +763,7 @@ fn (mut g Gen) is_gui_app() bool {
 	}
 	return false
 }
+
+fn (g &Gen) fileis(s string) bool {
+	return g.file.path.contains(s)
+}
diff --git a/vlib/v/parser/fn.v b/vlib/v/parser/fn.v
index c576ab129b..3fe6476efd 100644
--- a/vlib/v/parser/fn.v
+++ b/vlib/v/parser/fn.v
@@ -30,9 +30,15 @@ pub fn (mut p Parser) call_expr(language table.Language, mod string) ast.CallExp
 		// `foo<int>(10)`
 		p.next() // `<`
 		p.expr_mod = ''
-		generic_type = p.parse_type()
+		mut generic_type = p.parse_type()
+		if generic_type == table.t_type {
+			// Handle `foo<T>()`
+			// generic_type = p.cur_gen_type
+		}
 		p.check(.gt) // `>`
-		p.table.register_fn_gen_type(fn_name, generic_type)
+		if generic_type != table.t_type {
+			p.table.register_fn_gen_type(fn_name, generic_type)
+		}
 	}
 	p.check(.lpar)
 	args := p.call_args()
diff --git a/vlib/v/table/table.v b/vlib/v/table/table.v
index b0a876c5d8..417247e3f0 100644
--- a/vlib/v/table/table.v
+++ b/vlib/v/table/table.v
@@ -482,6 +482,6 @@ pub fn (table &Table) register_fn_gen_type(fn_name string, typ Type) {
 	}
 	a << typ
 	// sym := table.get_type_symbol(typ)
-	// println('registering fn gen type $sym.name')
+	// println('registering fn ($fn_name) gen type $sym.name')
 	table.fn_gen_types[fn_name] = a
 }
diff --git a/vlib/v/tests/generics_test.v b/vlib/v/tests/generics_test.v
index c03b9f0662..523b396039 100644
--- a/vlib/v/tests/generics_test.v
+++ b/vlib/v/tests/generics_test.v
@@ -210,6 +210,6 @@ fn test_generic_fn_with_variadics(){
 	p(s)
 	p(i)
 	p(abc)
-	p('Good','morning','world')
+	p('Good', 'morning', 'world')
 }
 */
diff --git a/vlib/vweb/vweb.v b/vlib/vweb/vweb.v
index e753a77f06..9772108f16 100644
--- a/vlib/vweb/vweb.v
+++ b/vlib/vweb/vweb.v
@@ -142,7 +142,7 @@ pub fn run<T>(port int) {
 	//app.reset()
 	for {
 		conn := l.accept() or { panic('accept() failed') }
-		handle_conn(conn, mut app)
+		handle_conn<T>(conn, mut app)
 		//foobar<T>()
 		// TODO move this to handle_conn<T>(conn, app)
 		//message := readall(conn)