normalize literal \r and \r\n chars in string literals to \n (fixes #…

…11988)

(cherry picked from commit fdec6bc)
ref #14073

src/julia-parser.scm

@@ -1831,6 +1831,14 @@
                (list* ex (tostr custom b) e)
                0)))
 
+      ; convert literal \r and \r\n in strings to \n (issue #11988)
+      ((eqv? c #\return) ; \r
+       (begin
+         (if (eqv? (peek-char p) #\linefeed) ; \r\n
+             (read-char p))
+         (write-char #\newline b)
+         (loop (read-char p) b e 0)))
+
       (else
        (write-char (not-eof-3 c) b)
        (loop (read-char p) b e 0)))))

test/parse.jl

@@ -304,3 +304,7 @@ let p = parse("try
     @test p.args[2] === false
     @test p.args[3].args[end] == parse("b,c = t")
 end
+
+# issue #11988 -- normalize \r and \r\n in literal strings to \n
+@test "foo\nbar" == parse("\"\"\"\r\nfoo\r\nbar\"\"\"") == parse("\"\"\"\nfoo\nbar\"\"\"") == parse("\"\"\"\rfoo\rbar\"\"\"") == parse("\"foo\r\nbar\"") == parse("\"foo\rbar\"") == parse("\"foo\nbar\"")
+@test '\r' == first("\r") == first("\r\n") # still allow explicit \r