From 31ffbc7a8727497d60f97dbf499c0106a519b191 Mon Sep 17 00:00:00 2001
From: yuyi <yuyi98@163.com>
Date: Thu, 6 Apr 2023 17:11:15 +0800
Subject: [PATCH] scanner: fix string interpolation string literal with fmt
 (#17895)

---
 vlib/v/scanner/scanner.v                      | 20 +++++++++++++------
 ...g_interpolation_string_lit_with_fmt_test.v |  6 ++++++
 2 files changed, 20 insertions(+), 6 deletions(-)
 create mode 100644 vlib/v/tests/string_interpolation_string_lit_with_fmt_test.v

diff --git a/vlib/v/scanner/scanner.v b/vlib/v/scanner/scanner.v
index 56b607c40c..872ec9a03a 100644
--- a/vlib/v/scanner/scanner.v
+++ b/vlib/v/scanner/scanner.v
@@ -34,6 +34,7 @@ pub mut:
 	last_nl_pos                 int = -1 // for calculating column
 	is_crlf                     bool   // special check when computing columns
 	is_inside_string            bool   // set to true in a string, *at the start* of an $var or ${expr}
+	is_nested_string            bool   // '${'abc':-12s}'
 	is_inter_start              bool   // for hacky string interpolation TODO simplify
 	is_inter_end                bool
 	is_enclosed_inter           bool
@@ -268,7 +269,7 @@ fn (mut s Scanner) ident_bin_number() string {
 			s.error('cannot use `_` consecutively')
 		}
 		if !c.is_bin_digit() && c != scanner.num_sep {
-			if (!c.is_digit() && !c.is_letter()) || s.is_inside_string {
+			if (!c.is_digit() && !c.is_letter()) || s.is_inside_string || s.is_nested_string {
 				break
 			} else if !has_wrong_digit {
 				has_wrong_digit = true
@@ -312,7 +313,7 @@ fn (mut s Scanner) ident_hex_number() string {
 			s.error('cannot use `_` consecutively')
 		}
 		if !c.is_hex_digit() && c != scanner.num_sep {
-			if !c.is_letter() || s.is_inside_string {
+			if !c.is_letter() || s.is_inside_string || s.is_nested_string {
 				break
 			} else if !has_wrong_digit {
 				has_wrong_digit = true
@@ -352,7 +353,7 @@ fn (mut s Scanner) ident_oct_number() string {
 			s.error('cannot use `_` consecutively')
 		}
 		if !c.is_oct_digit() && c != scanner.num_sep {
-			if (!c.is_digit() && !c.is_letter()) || s.is_inside_string {
+			if (!c.is_digit() && !c.is_letter()) || s.is_inside_string || s.is_nested_string {
 				break
 			} else if !has_wrong_digit {
 				has_wrong_digit = true
@@ -390,7 +391,7 @@ fn (mut s Scanner) ident_dec_number() string {
 			s.error('cannot use `_` consecutively')
 		}
 		if !c.is_digit() && c != scanner.num_sep {
-			if !c.is_letter() || c in [`e`, `E`] || s.is_inside_string {
+			if !c.is_letter() || c in [`e`, `E`] || s.is_inside_string || s.is_nested_string {
 				break
 			} else if !has_wrong_digit {
 				has_wrong_digit = true
@@ -415,7 +416,8 @@ fn (mut s Scanner) ident_dec_number() string {
 				for s.pos < s.text.len {
 					c := s.text[s.pos]
 					if !c.is_digit() {
-						if !c.is_letter() || c in [`e`, `E`] || s.is_inside_string {
+						if !c.is_letter() || c in [`e`, `E`] || s.is_inside_string
+							|| s.is_nested_string {
 							// 5.5.str()
 							if c == `.` && s.pos + 1 < s.text.len && s.text[s.pos + 1].is_letter() {
 								call_method = true
@@ -461,7 +463,7 @@ fn (mut s Scanner) ident_dec_number() string {
 		for s.pos < s.text.len {
 			c := s.text[s.pos]
 			if !c.is_digit() {
-				if !c.is_letter() || s.is_inside_string {
+				if !c.is_letter() || s.is_inside_string || s.is_nested_string {
 					// 5e5.str()
 					if c == `.` && s.pos + 1 < s.text.len && s.text[s.pos + 1].is_letter() {
 						call_method = true
@@ -1130,6 +1132,12 @@ fn (s &Scanner) count_symbol_before(p int, sym u8) int {
 
 [direct_array_access]
 fn (mut s Scanner) ident_string() string {
+	// determines if it is a nested string
+	if s.is_inside_string {
+		s.is_nested_string = true
+	} else {
+		s.is_nested_string = false
+	}
 	lspos := token.Pos{
 		line_nr: s.line_nr
 		pos: s.pos
diff --git a/vlib/v/tests/string_interpolation_string_lit_with_fmt_test.v b/vlib/v/tests/string_interpolation_string_lit_with_fmt_test.v
new file mode 100644
index 0000000000..93b8c3d8e4
--- /dev/null
+++ b/vlib/v/tests/string_interpolation_string_lit_with_fmt_test.v
@@ -0,0 +1,6 @@
+fn test_string_interpolation_string_lit_with_fmt() {
+	println('${'hello':-12s}')
+	assert '${'hello':-12s}' == 'hello       '
+	println('${'hello':12s}')
+	assert '${'hello':12s}' == '       hello'
+}