This patch is part of universal parser work.
## Summary
- Decouple VALUE from members below:
- `(struct parser_params *)->debug_lines`
- `(rb_ast_t *)->body.script_lines`
- Instead, they are now `rb_parser_ary_t *`
- They can also be a `(VALUE)FIXNUM` as before to hold line count
- `ISEQ_BODY(iseq)->variable.script_lines` remains VALUE
- In order to do this,
- Add `VALUE script_lines` param to `rb_iseq_new_with_opt()`
- Introduce `rb_parser_build_script_lines_from()` to convert `rb_parser_ary_t *` into `VALUE`
## Other details
- Extend `rb_parser_ary_t *`. It previously could only store `rb_parser_ast_token *`, now can store script_lines, too
- Change tactics of building the top-level `SCRIPT_LINES__` in `yycompile0()`
- Before: While parsing, each line of the script is added to `SCRIPT_LINES__[path]`
- After: After `yyparse(p)`, `SCRIPT_LINES__[path]` will be built from `p->debug_lines`
- Remove the second parameter of `rb_parser_set_script_lines()` to make it simple
- Introduce `script_lines_free()` to be called from `rb_ast_free()` because the GC no longer takes care of the script_lines
- Introduce `rb_parser_string_deep_copy()` in parse.y to maintain script_lines when `rb_ruby_parser_free()` called
- With regard to this, please see *Future tasks* below
## Future tasks
- Decouple IMEMO from `rb_ast_t *`
- This lifts the five-members-restriction of Ruby object,
- So we will be able to move the ownership of the `lex.string_buffer` from parser to AST
- Then we remove `rb_parser_string_deep_copy()` to make the whole thing simple
The `rb_fstring(rb_enc_str_new())` pattern is inneficient because:
- It passes a mutable string to `rb_fstring` so if it has to be interned
it will first be duped.
- It an equivalent interned string already exists, we allocated the string
for nothing.
With `rb_enc_interned_str` we either directly get the pre-existing string
with 0 allocations, or efficiently directly intern the one we create
without first duping it.
This patch suggests relocating the code dealing with `SCRIPT_LINES__` from ast.c to ruby_parser.c.
## Background
- I guess `AbstractSyntaxTree.of` method used to use `SCRIPT_LINES__` internally for some reason before
- However, now it appears `SCRIPT_LINES__` is no longer used meaningfully by the method
- As evidence of this, (and as my patch shows,) removing the function call of `rb_script_lines_for()` from `ast_s_of()` does not affect the result of `test/ruby/test_ast.rb`
Given the above, I think two possibilities can be considered:
- (A) `AbstractSyntaxTree.of` has not needed `SCRIPT_LINES__` already (I pick this)
- (B) We lack a test case of `AbstractSyntaxTree.of` that needs to use `SCRIPT_LINES__`
## Besides,
The current implementation causes strange behavior:
```console
ruby -e"SCRIPT_LINES__ = {__FILE__ => []}; puts RubyVM::AbstractSyntaxTree.of(->{ 1 + 2 }, keep_script_lines: true).script_lines"
=> `-e:1:in '<main>': undefined method 'script_lines' for nil (NoMethodError)`
```
I think this is a bug because `AbstractSyntaxTree.of` is not supposed to return `nil` even in this case.
This happens due to the ast.c's dependence on `SCRIPT_LINES__`.
And at the end of the `ast_s_of()`, `node_find()` can not find the target child node obviously because it doesn't make sense to look for a corresponding node made from the parameter of `AbstractSyntaxTree.of` in the AST tree made from the value of `{__FILE__ => []}`
## Solution
Since I think it's good enough `SCRIPT_LINES__` to be only referred by ruby.c, I chose the possibility "(A)" and wrote this patch which moves `rb_script_lines_for()` from ast.c to ruby_parser.c.
So as the result:
- `ast_s_of()` function no longer look up `SCRIPT_LINES__`
- Even so, this patched code passes the existing tests
- The strange behavior above no longer happens (I also added a test for it)
Please correct me if I miss something🙏
This commit simplifies warnings for hash keys duplication and when clause duplication,
based on the discussion of https://bugs.ruby-lang.org/issues/20331.
Warnings are reported only when strings are same to ohters.
- Introduce `rb_parser_ary_t` structure to partly eliminate RArray from parse.y
- In this patch, `parser_params->tokens` and `parser_params->ast->node_buffer->tokens` are now `rb_parser_ary_t *`
- Instead, `ast_node_all_tokens()` internally creates a Ruby Array object from the `rb_parser_ary_t`
- Also, delete `rb_ast_tokens()` and `rb_ast_set_tokens()` in node.c
- Implement `rb_parser_str_escape()`
- This is a port of the `rb_str_escape()` function in string.c
- `rb_parser_str_escape()` does not depend on `VALUE` (RString)
- Instead, it uses `rb_parser_stirng_t *`
- This function works when --dump=y option passed
- Because WIP of the universal parser, similar functions like `rb_parser_tokens_free()` exist in both node.c and parse.y. Refactoring them may be needed in some way in the future
- Although we considered redesigning the structure: `ast->node_buffer->tokens` into `ast->tokens`, we leave it as it is because `rb_ast_t` is an imemo. (We will address it in the future)
Rather than exposing that an imemo has a flag and four fields, this
changes the implementation to only expose one field (the klass) and
fills the rest with 0. The type will have to fill in the values themselves.
`dest` of `const_decl_path` is `NODE_COLON2` or `NODE_COLON3` in some cases.
For example, `B::C ||= [“Not ” + “shareable”]` passes `NODE_COLON2`
and `::C ||= [“Not ” + “shareable”]` passes `NODE_COLON3`.
This commit fixes `Ractor::IsolationError` message for such case.
```
# shareable_constant_value: literal
::C ||= ["Not " + "shareable"]
# Before
# => cannot assign unshareable object to C (Ractor::IsolationError)
# After
# => cannot assign unshareable object to ::C (Ractor::IsolationError)
```
If lhs of assignment is top-level constant reference, the first
constant name is omitted from error message.
This commit fixes it.
```
# shareable_constant_value: literal
::C = ["Not " + "shareable"]
# Before
# => cannot assign unshareable object to (Ractor::IsolationError)
# After
# => cannot assign unshareable object to ::C (Ractor::IsolationError)
```
String nodes holds ruby string object on `VALUE nd_lit`.
This commit changes it to `struct rb_parser_string *string`
to reduce dependency on ruby object.
Sometimes these strings are concatenated with other string
therefore string concatenate functions are needed.
`__ENCODING__ `was managed by `NODE_LIT` with Encoding object.
Introduce `NODE_ENCODING` for
1. `__ENCODING__` is detectable from AST Node.
2. Reduce dependency Ruby object for parse.y
This commit changes `struct parser_params` lastline and nextline
from `VALUE` (String object) to `rb_parser_string_t *` so that
dependency on Ruby Object is reduced.
`parser_string_buffer_t string_buffer` is added to `struct parser_params`
to manage `rb_parser_string_t` pointers of each line. All allocated line
strings are freed in `rb_ruby_parser_free`.
`:sym` was managed by `NODE_LIT` with `Symbol` object.
This commit introduces `NODE_SYM` so that
1. Symbol literal is detectable from AST Node
2. Reduce dependency on ruby object
`__FILE__` was managed by `NODE_STR` with `String` object.
This commit introduces `NODE_FILE` and `struct rb_parser_string` so that
1. `__FILE__` is detectable from AST Node
2. Reduce dependency ruby object
