From 1f74f83bc66fcf23e6605ea8c9e60b88dc760656 Mon Sep 17 00:00:00 2001
From: Alexander Medvednikov <alexander@vlang.io>
Date: Sat, 19 Dec 2020 10:28:17 +0100
Subject: [PATCH] parser: map or block; checker: require ref field init

---
 vlib/builtin/map_test.v  | 27 ++++++++++++++++++---------
 vlib/v/ast/ast.v         |  1 +
 vlib/v/checker/checker.v |  2 +-
 vlib/v/parser/fn.v       |  2 +-
 vlib/v/parser/parser.v   | 24 ++++++++++++++++++++++++
 vlib/v/parser/pratt.v    |  2 +-
 6 files changed, 46 insertions(+), 12 deletions(-)

diff --git a/vlib/builtin/map_test.v b/vlib/builtin/map_test.v
index 83c5a2b934..17c359b129 100644
--- a/vlib/builtin/map_test.v
+++ b/vlib/builtin/map_test.v
@@ -404,9 +404,9 @@ fn test_mut_map_with_relation_op_in_fn() {
 
 fn test_map_str_after_delete() {
 	mut m := {
-		'first': 1
+		'first':  1
 		'second': 2
-		'third': 3
+		'third':  3
 	}
 	osm := '$m'
 	m.delete('second')
@@ -429,7 +429,7 @@ fn test_modify_map_value() {
 
 fn test_map_clone() {
 	mut nums := {
-		'foo': 1,
+		'foo': 1
 		'bar': 2
 	}
 	mut nums2 := nums.clone()
@@ -442,14 +442,23 @@ fn test_map_clone() {
 }
 
 struct MValue {
-    name string
-    misc map[string]string
+	name string
+	misc map[string]string
 }
 
 fn test_map_default_zero() {
-    m := map[string]MValue{}
-    v := m['unknown']
-    x := v.misc['x']
-    println(x)
+	m := map[string]MValue{}
+	v := m['unknown']
+	x := v.misc['x']
+	println(x)
 	assert x == ''
 }
+
+fn test_map_or() {
+	m := {
+		'first':  1
+		'second': 2
+		'third':  3
+	}
+	// num := m['first'] or { return }
+}
diff --git a/vlib/v/ast/ast.v b/vlib/v/ast/ast.v
index cefe86dfcc..29e1efaa76 100644
--- a/vlib/v/ast/ast.v
+++ b/vlib/v/ast/ast.v
@@ -524,6 +524,7 @@ pub:
 	pos       token.Position
 	left      Expr
 	index     Expr // [0], RangeExpr [start..end] or map[key]
+	or_expr   OrExpr
 pub mut:
 	left_type table.Type // array, map, fixed array
 	is_setter bool
diff --git a/vlib/v/checker/checker.v b/vlib/v/checker/checker.v
index fe53336286..886e4d949e 100644
--- a/vlib/v/checker/checker.v
+++ b/vlib/v/checker/checker.v
@@ -591,7 +591,7 @@ pub fn (mut c Checker) struct_init(mut struct_init ast.StructInit) table.Type {
 					continue
 				}
 				if field.typ.is_ptr() && !c.pref.translated {
-					c.warn('reference field `${type_sym.name}.$field.name` must be initialized',
+					c.error('reference field `${type_sym.name}.$field.name` must be initialized',
 						struct_init.pos)
 				}
 				// Check for `[required]` struct attr
diff --git a/vlib/v/parser/fn.v b/vlib/v/parser/fn.v
index 32a924323e..2e2c6f1b4d 100644
--- a/vlib/v/parser/fn.v
+++ b/vlib/v/parser/fn.v
@@ -54,7 +54,7 @@ pub fn (mut p Parser) call_expr(language table.Language, mod string) ast.CallExp
 		p.next()
 	}
 	pos := first_pos.extend(last_pos)
-	mut or_stmts := []ast.Stmt{}
+	mut or_stmts := []ast.Stmt{} // TODO remove unnecessary allocations by just using .absent
 	mut or_pos := p.tok.position()
 	if p.tok.kind == .key_orelse {
 		// `foo() or {}``
diff --git a/vlib/v/parser/parser.v b/vlib/v/parser/parser.v
index 535269d203..41f22e8b2e 100644
--- a/vlib/v/parser/parser.v
+++ b/vlib/v/parser/parser.v
@@ -1326,10 +1326,34 @@ fn (mut p Parser) index_expr(left ast.Expr) ast.IndexExpr {
 	// [expr]
 	pos := start_pos.extend(p.tok.position())
 	p.check(.rsbr)
+	// a[i] or { ... }
+	if p.tok.kind == .key_orelse {
+		was_inside_or_expr := p.inside_or_expr
+		mut or_pos := p.tok.position()
+		p.next()
+		p.open_scope()
+		or_stmts := p.parse_block_no_scope(false)
+		or_pos = or_pos.extend(p.prev_tok.position())
+		p.close_scope()
+		p.inside_or_expr = was_inside_or_expr
+		return ast.IndexExpr{
+			left: left
+			index: expr
+			pos: pos
+			or_expr: ast.OrExpr{
+				kind: .block
+				stmts: or_stmts
+				pos: or_pos
+			}
+		}
+	}
 	return ast.IndexExpr{
 		left: left
 		index: expr
 		pos: pos
+		or_expr: ast.OrExpr{
+			kind: .absent
+		}
 	}
 }
 
diff --git a/vlib/v/parser/pratt.v b/vlib/v/parser/pratt.v
index 3207d8892c..debe374b27 100644
--- a/vlib/v/parser/pratt.v
+++ b/vlib/v/parser/pratt.v
@@ -244,7 +244,7 @@ pub fn (mut p Parser) expr(precedence int) ast.Expr {
 		else {
 			if p.tok.kind != .eof {
 				// eof should be handled where it happens
-				p.error_with_pos('invalid expression: unexpected $p.tok.kind.str() token',
+				p.error_with_pos('invalid expression: unexpected `$p.tok.kind.str()` token',
 					p.tok.position())
 				return ast.Expr{}
 			}