New location tracking Location, SpanManager

[ehwan]

• New location system that is not depending on proc_macro2
• Added unit tests
• Fixed deterministic & nondeterministic context stack calculation bug

[gemini-code-assist]

Code Review

This pull request refactors the location tracking system across the codebase to use a new Location and SpanManager infrastructure instead of raw proc_macro2::Span or SpanPair. This change allows mapping byte ranges back to spans for more precise error reporting. Deterministic and non-deterministic parser contexts have been updated to pass Location directly rather than wrapping it in an Option, and error types now hold a non-optional Location. Additionally, the lexer, parser, grammar, and pattern modules have been updated to use Located<T> and Location. A minor issue was found in rusty_lr_core/src/parser/nondeterministic/context.rs where a doc comment is duplicated on consecutive lines.

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[Copilot]

Pull request overview

This PR refactors RustyLR’s location tracking to use a new Location + SpanManager mechanism (index ranges into a collected span table) instead of the previous SpanPair approach, and updates parsing/error-reporting/codegen paths accordingly. It also adjusts deterministic/nondeterministic parser contexts to compute default locations more consistently (including EOF) and adds unit tests validating error recovery + EOF location behavior in the JSON example.

Changes:

• Replace %location SpanPair with %location Location and introduce parser::location::{Location, Located, SpanManager} for mapping locations to spans/byte ranges.
• Update grammar parsing, pattern/terminal-set handling, error types, and code emission to use Location/Located<T> throughout.
• Fix context/tag-stack truncation logic and add bootstrap/test coverage (including JSON example unit tests).

Reviewed changes

Copilot reviewed 31 out of 32 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
scripts/diff/json.rs	Regenerated JSON diff output reflecting new literal/terminal-set printing and userdata location capture.
scripts/diff/calculator.rs	Regenerated calculator diff output; includes tag-stack handling fixes.
scripts/diff/calculator_u8.rs	Regenerated u8 calculator diff output; includes naming + tag-stack truncation fixes.
scripts/bootstrap_test.sh	Runs cargo test during bootstrap comparisons to validate generated output builds/tests.
rusty_lr_parser/src/utils.rs	Switch helper utilities to the new Location/SpanManager-based identifier construction.
rusty_lr_parser/src/token.rs	Replace proc-macro spans with Location and make mapto location-aware (Located<String>).
rusty_lr_parser/src/terminalset.rs	Convert terminal-set AST to use Located<T> + Location for error reporting and ranges.
rusty_lr_parser/src/terminal_info.rs	Make terminal identifiers string-based and store precedence with Located<usize>.
rusty_lr_parser/src/pattern.rs	Update pattern lowering to use Location and typed literals (Byte/Char/String/...).
rusty_lr_parser/src/parser/span_pair.rs	Removed old SpanPair location mechanism.
rusty_lr_parser/src/parser/parser.rs	Update grammar parser rules/tokens to emit Location + typed literals.
rusty_lr_parser/src/parser/mod.rs	Register new location module; drop span_pair module.
rusty_lr_parser/src/parser/location.rs	New location system (Location, Located<T>, SpanManager) + unit tests.
rusty_lr_parser/src/parser/lexer.rs	Collect spans into SpanManager and feed Location instead of SpanPair.
rusty_lr_parser/src/parser/args.rs	Update grammar-arg structures to store Location/Located<T>; refine precedence/literal handling.
rusty_lr_parser/src/nonterminal_info.rs	Store nonterminal names and rule metadata using Location/Located.
rusty_lr_parser/src/lib.rs	Re-export Location for external consumers.
rusty_lr_parser/src/error.rs	Refactor errors to use Location and emit diagnostics via SpanManager.
rusty_lr_parser/src/emit.rs	Emit generated code using correct spans derived from SpanManager locations.
rusty_lr_parser/Cargo.toml	Enable proc-macro2 span-locations feature to support byte-range mapping.
rusty_lr_derive/src/lib.rs	Thread SpanManager through error emission in the proc-macro entrypoint.
rusty_lr_core/src/rule.rs	Minor doc formatting change.
rusty_lr_core/src/parser/nondeterministic/error.rs	Make parse error location non-optional.
rusty_lr_core/src/parser/nondeterministic/context.rs	Compute default locations (incl. EOF) from stacks and align stack behavior.
rusty_lr_core/src/parser/deterministic/error.rs	Make parse error location non-optional.
rusty_lr_core/src/parser/deterministic/context.rs	Compute default locations from stacks and always push locations (incl. EOF).
rusty_lr_buildscript/src/utils.rs	Remove old byte-range helpers now superseded by SpanManager.
rusty_lr_buildscript/src/lib.rs	Switch diagnostics to use SpanManager for byte-range extraction from Location.
example/json/src/parser.rs	Use userdata to capture recovered error locations instead of printing.
example/json/src/main.rs	Pass userdata through parsing and add unit tests for success, recovery location, and EOF location.

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