[ruby/prism] Fix parsing heredoc ends

https://github.com/ruby/prism/commit/aa8c702271

4 files changed, 80 insertions, 0 deletions

diff --git a/test/prism/fixtures/heredocs_leading_whitespace.txt b/test/prism/fixtures/heredocs_leading_whitespace.txt
new file mode 100644
index 0000000000..e786f08774
--- /dev/null
+++ b/test/prism/fixtures/heredocs_leading_whitespace.txt
@@ -0,0 +1,19 @@
+<<-'  FOO'
+a
+b
+     FOO
+
+<<-'  FOO'
+a
+b
+  FOO
+
+<<~'  FOO'
+a
+b
+     FOO
+
+<<~'  FOO'
+a
+b
+  FOO
diff --git a/test/prism/locals_test.rb b/test/prism/locals_test.rb
index 06324f9d94..df391ca048 100644
--- a/test/prism/locals_test.rb
+++ b/test/prism/locals_test.rb
@@ -68,6 +68,13 @@ module Prism
     # HERE
     todos << "seattlerb/heredoc_nested.txt"
 
+    # Ruby < 3.3.0 fails to parse:
+    #
+    # <<-'  HERE'
+    #  foo
+    #   HERE
+    invalid << "heredocs_leading_whitespace.txt" if RUBY_VERSION < "3.3.0"
+
     base = File.join(__dir__, "fixtures")
     skips = invalid | todos
 
diff --git a/test/prism/parse_test.rb b/test/prism/parse_test.rb
index 2feb15b48b..e2de55463c 100644
--- a/test/prism/parse_test.rb
+++ b/test/prism/parse_test.rb
@@ -111,6 +111,11 @@ module Prism
       # Additionally, Ripper cannot parse the %w[] fixture in this file, so set ripper_should_parse to false.
       ripper_should_parse = false if relative == "spanning_heredoc.txt"
 
+      # Ruby < 3.3.0 cannot parse heredocs where there are leading whitespace charactes in the heredoc start.
+      # Example: <<~'   EOF' or <<-'  EOF'
+      # https://bugs.ruby-lang.org/issues/19539
+      ripper_should_parse = false if relative == "heredocs_leading_whitespace.txt" && RUBY_VERSION < "3.3.0"
+
       define_method "test_filepath_#{relative}" do
         # First, read the source from the filepath. Use binmode to avoid converting CRLF on Windows,
         # and explicitly set the external encoding to UTF-8 to override the binmode default.
diff --git a/test/prism/snapshots/heredocs_leading_whitespace.txt b/test/prism/snapshots/heredocs_leading_whitespace.txt
new file mode 100644
index 0000000000..06116821ca
--- /dev/null
+++ b/test/prism/snapshots/heredocs_leading_whitespace.txt
@@ -0,0 +1,49 @@
+@ ProgramNode (location: (1,0)-(16,10))
+├── locals: []
+└── statements:
+    @ StatementsNode (location: (1,0)-(16,10))
+    └── body: (length: 4)
+        ├── @ StringNode (location: (1,0)-(1,10))
+        │   ├── flags: ∅
+        │   ├── opening_loc: (1,0)-(1,10) = "<<-'  FOO'"
+        │   ├── content_loc: (2,0)-(4,0) = "a\nb\n"
+        │   ├── closing_loc: (4,0)-(5,0) = "     FOO\n"
+        │   └── unescaped: "a\nb\n"
+        ├── @ StringNode (location: (6,0)-(6,10))
+        │   ├── flags: ∅
+        │   ├── opening_loc: (6,0)-(6,10) = "<<-'  FOO'"
+        │   ├── content_loc: (7,0)-(9,0) = "a\nb\n"
+        │   ├── closing_loc: (9,0)-(10,0) = "  FOO\n"
+        │   └── unescaped: "a\nb\n"
+        ├── @ InterpolatedStringNode (location: (11,0)-(11,10))
+        │   ├── opening_loc: (11,0)-(11,10) = "<<~'  FOO'"
+        │   ├── parts: (length: 2)
+        │   │   ├── @ StringNode (location: (12,0)-(13,0))
+        │   │   │   ├── flags: ∅
+        │   │   │   ├── opening_loc: ∅
+        │   │   │   ├── content_loc: (12,0)-(13,0) = "a\n"
+        │   │   │   ├── closing_loc: ∅
+        │   │   │   └── unescaped: "a\n"
+        │   │   └── @ StringNode (location: (13,0)-(14,0))
+        │   │       ├── flags: ∅
+        │   │       ├── opening_loc: ∅
+        │   │       ├── content_loc: (13,0)-(14,0) = "b\n"
+        │   │       ├── closing_loc: ∅
+        │   │       └── unescaped: "b\n"
+        │   └── closing_loc: (14,0)-(15,0) = "     FOO\n"
+        └── @ InterpolatedStringNode (location: (16,0)-(16,10))
+            ├── opening_loc: (16,0)-(16,10) = "<<~'  FOO'"
+            ├── parts: (length: 2)
+            │   ├── @ StringNode (location: (17,0)-(18,0))
+            │   │   ├── flags: ∅
+            │   │   ├── opening_loc: ∅
+            │   │   ├── content_loc: (17,0)-(18,0) = "a\n"
+            │   │   ├── closing_loc: ∅
+            │   │   └── unescaped: "a\n"
+            │   └── @ StringNode (location: (18,0)-(19,0))
+            │       ├── flags: ∅
+            │       ├── opening_loc: ∅
+            │       ├── content_loc: (18,0)-(19,0) = "b\n"
+            │       ├── closing_loc: ∅
+            │       └── unescaped: "b\n"
+            └── closing_loc: (19,0)-(20,0) = "  FOO\n"