From d3b8c9bf3bba9b53ede7b3685ebe9a120a36c7a0 Mon Sep 17 00:00:00 2001
From: CreeperFace <165158232+dy-tea@users.noreply.github.com>
Date: Sun, 28 Dec 2025 21:21:52 +0000
Subject: [PATCH] checker,vls: support gotodef for fn param and []Type (#26193)

---
 vlib/v/checker/fn.v                    | 12 +++++
 vlib/v/checker/struct.v                | 29 +++++++++--
 vlib/v/tests/vls/goto_def_test.v       | 66 ++++++++++++++++++++++++++
 vlib/v/tests/vls/goto_def_test_data.vv | 21 ++++++++
 4 files changed, 124 insertions(+), 4 deletions(-)

diff --git a/vlib/v/checker/fn.v b/vlib/v/checker/fn.v
index cc9b41e4d..7910a2cf5 100644
--- a/vlib/v/checker/fn.v
+++ b/vlib/v/checker/fn.v
@@ -311,6 +311,18 @@ fn (mut c Checker) fn_decl(mut node ast.FnDecl) {
 	if node.language == .v {
 		// Make sure all types are valid
 		for mut param in node.params {
+			// handle vls go to definition for parameter types
+			if c.pref.is_vls && c.pref.linfo.method == .definition {
+				if c.vls_is_the_node(param.type_pos) {
+					typ_str := c.table.type_to_str(param.typ)
+					if np := c.name_pos_gotodef(typ_str) {
+						if np.file_idx != -1 {
+							println('${c.table.filelist[np.file_idx]}:${np.line_nr + 1}:${np.col}')
+						}
+						exit(0)
+					}
+				}
+			}
 			if !c.ensure_type_exists(param.typ, param.type_pos) {
 				return
 			}
diff --git a/vlib/v/checker/struct.v b/vlib/v/checker/struct.v
index adcbe384d..0763042fc 100644
--- a/vlib/v/checker/struct.v
+++ b/vlib/v/checker/struct.v
@@ -190,10 +190,31 @@ fn (mut c Checker) struct_decl(mut node ast.StructDecl) {
 			if c.pref.is_vls && c.pref.linfo.method == .definition {
 				if c.vls_is_the_node(field.type_pos) {
 					sym := c.table.sym(field.typ)
-					pos := sym.info.get_name_pos() or { token.Pos{} }
-					if pos.file_idx != -1 {
-						println('${c.table.filelist[pos.file_idx]}:${pos.line_nr + 1}:${pos.col}')
-						exit(0)
+					elem_type := match sym.kind {
+						.array {
+							(sym.info as ast.Array).elem_type
+						}
+						.array_fixed {
+							(sym.info as ast.ArrayFixed).elem_type
+						}
+						else {
+							ast.Type(0)
+						}
+					}
+					if elem_type == 0 {
+						pos := sym.info.get_name_pos() or { token.Pos{} }
+						if pos.file_idx != -1 {
+							println('${c.table.filelist[pos.file_idx]}:${pos.line_nr + 1}:${pos.col}')
+							exit(0)
+						}
+					} else {
+						elem_sym := c.table.sym(elem_type)
+						if np := elem_sym.info.get_name_pos() {
+							if np.file_idx != -1 {
+								println('${c.table.filelist[np.file_idx]}:${np.line_nr + 1}:${np.col}')
+								exit(0)
+							}
+						}
 					}
 				}
 			}
diff --git a/vlib/v/tests/vls/goto_def_test.v b/vlib/v/tests/vls/goto_def_test.v
index 46329cfc3..2d404c51c 100644
--- a/vlib/v/tests/vls/goto_def_test.v
+++ b/vlib/v/tests/vls/goto_def_test.v
@@ -198,6 +198,72 @@ const test_cases = [
 		expected:    '${mod1_text_file}:25:1'
 		description: 'Go to imported enum value definition'
 	},
+	// test_operator_overload() tests
+	TestCase{
+		name:        'operator_receiver_type'
+		line:        137
+		col:         8
+		expected:    '${test_file}:133:7'
+		description: 'Go to struct definition from operator overload receiver type'
+	},
+	TestCase{
+		name:        'operator_param_type'
+		line:        137
+		col:         22
+		expected:    '${test_file}:133:7'
+		description: 'Go to struct definition from operator overload parameter type'
+	},
+	TestCase{
+		name:        'operator_return_type'
+		line:        137
+		col:         33
+		expected:    '${test_file}:133:7'
+		description: 'Go to struct definition from operator overload return type'
+	},
+	TestCase{
+		name:        'struct_init_field_in_params_left'
+		line:        138
+		col:         23
+		expected:    '${test_file}:137:4'
+		description: 'Go to param definition from struct init variable (left fn param)'
+	},
+	TestCase{
+		name:        'struct_init_field_in_params_right'
+		line:        138
+		col:         31
+		expected:    '${test_file}:137:19'
+		description: 'Go to param definition from struct init variable (right fn param)'
+	},
+	TestCase{
+		name:        'field_selector_in_struct_init'
+		line:        138
+		col:         25
+		expected:    '${test_file}:134:1'
+		description: 'Go to field definition from selector expression in struct init value (a.val)'
+	},
+	// test_function_params() tests
+	TestCase{
+		name:        'function_param_type'
+		line:        141
+		col:         24
+		expected:    '${test_file}:133:7'
+		description: 'Go to struct definition from function parameter type'
+	},
+	// test_array_field_types() tests
+	TestCase{
+		name:        'array_elem_type_in_struct_field'
+		line:        150
+		col:         10
+		expected:    '${test_file}:145:7'
+		description: 'Go to element type definition from array type in struct field ([]ArrayElemStruct)'
+	},
+	TestCase{
+		name:        'fixed_array_elem_type_in_struct_field'
+		line:        151
+		col:         17
+		expected:    '${test_file}:145:7'
+		description: 'Go to element type definition from fixed array type in struct field ([5]ArrayElemStruct)'
+	},
 ]
 
 fn test_goto_definition() {
diff --git a/vlib/v/tests/vls/goto_def_test_data.vv b/vlib/v/tests/vls/goto_def_test_data.vv
index 9351ff1cc..8fe329585 100644
--- a/vlib/v/tests/vls/goto_def_test_data.vv
+++ b/vlib/v/tests/vls/goto_def_test_data.vv
@@ -129,3 +129,24 @@ fn test_imported_enum() {
 	imported_e := s.PublicEnum1.a
 	println(imported_e)
 }
+
+struct OpStruct {
+	val int
+}
+
+fn (a OpStruct) + (b OpStruct) OpStruct {
+	return OpStruct{val: a.val + b.val}
+}
+
+fn takes_struct(param OpStruct) string {
+	return param.str()
+}
+
+struct ArrayElemStruct {
+	value int
+}
+
+struct ContainerStruct {
+	items []ArrayElemStruct
+	fixed_items [5]ArrayElemStruct
+}
-- 
2.39.5