Merge pull request #41930 from hamishknight/quoted-in-context

Author: hamishknight

test/StringProcessing/Parse/regex.swift

@@ -21,3 +21,11 @@ _ = re're\r\e\'\\'
 _ = (#/[*/#, #/+]/#, #/.]/#)
 // expected-error@-1 {{cannot parse regular expression: quantifier '+' must appear after expression}}
 // expected-error@-2 {{cannot parse regular expression: expected ']'}}
+
+// Make sure we can skip over `'` characters in the regex body.
+_ = re'(?'xA0_-y1'x)'
+_ = re'(?('xA0_')\')'
+_ = re'\'(?('-20'))'
+_ = re'\k'+2-1'\''
+_ = re'\g'xA0_''
+_ = re'(?C'9,3, pg(')'

test/StringProcessing/Parse/regex_parse_error.swift

@@ -6,10 +6,43 @@ _ = re'(' // expected-error {{expected ')'}}
 // FIXME: Should be 'group openings'
 _ = re')' // expected-error {{closing ')' does not balance any groups openings}}
 
-let s = #/\\/''/ // expected-error {{unterminated regex literal}}
+_ = #/\\/''/ // expected-error {{unterminated regex literal}}
 _ = #|\| // expected-error {{unterminated regex literal}}
 _ = #// // expected-error {{unterminated regex literal}}
 _ = re'x // expected-error {{unterminated regex literal}}
 
-// expected-error@+1 {{unterminated regex literal}}
-var unterminated = #/xy
+_ = #/xy // expected-error {{unterminated regex literal}}
+
+_ = re'(?' // expected-error {{expected group specifier}}
+
+_ = re'(?'' // expected-error {{unterminated regex literal}}
+// expected-error@-1 {{expected group name}}
+
+_ = re'(?'abc' // expected-error {{unterminated regex literal}}
+// expected-error@-1 {{expected ')'}}
+
+// TODO: Maybe change "unterminated string literal" to "unterminated single quote"?
+_ = re'(?'abc ' // expected-error {{unterminated string literal}}
+// expected-error@-1 {{expected group specifier}}
+// expected-error@-2 {{consecutive statements on a line must be separated by ';'}}
+
+_ = re'(?'a // expected-error {{expected group specifier}}
+// expected-error@-1 {{cannot find 'a' in scope}}
+// expected-error@-2 {{consecutive statements on a line must be separated by ';'}}
+
+_ = re'\(?'abc' // expected-error {{unterminated string literal}}
+// expected-error@-1 {{consecutive statements on a line must be separated by ';'}}
+
+ _ = re'\
+ '
+// expected-error@-2 {{unterminated regex literal}}
+// expected-error@-3 {{expected escape sequence}}
+// expected-error@-3 {{unterminated string literal}}
+
+func foo<T>(_ x: T, _ y: T) {}
+foo(re'(?', re'abc') // expected-error {{expected group specifier}}
+foo(re'(?C', re'abc') // expected-error {{expected ')'}}
+
+foo(re'(?'', re'abc') // expected-error {{expected group name}}
+// expected-error@-1 {{unterminated string literal}}
+// expected-error@-2 {{expected ',' separator}}