[nyurik]

This PR includes #127 which should be merged first

In a case with duplicate names:

VAL_TABLE_ Bar 6 "reserved" 5 "reserved" 4 "unused 2" 3 "unused" 2 "unused" 1 "#%=*�'" 0 "With space" -5 "A negative value" ;
VAL_ 0 Foo 6 "reserved" 5 "reserved" 4 "unused 2" 3 "unused" 2 "unused" 1 "#%=*�'" 0 "With space" -5 "A negative value" ;

generate parametrized enum instead:

match signal {
    6 => FooFoo::Reserved(6),
    5 => FooFoo::Reserved(5),
    4 => FooFoo::Unused2,
    3 => FooFoo::Unused(3),
    2 => FooFoo::Unused(2),
    1 => FooFoo::XÄ,
    0 => FooFoo::WithSpace,
    -5 => FooFoo::ANegativeValue,
    _ => FooFoo::_Other(self.foo_raw()),
}

• use appropriate signed type too: u8 -> i8

let signal = self.raw.view_bits::<Lsb0>()[0..8].load_le::<i8>();

• streamline multiplex indicator handling and enhance enum variant generation

[nyurik]

@rnd-ash does this solve your #98 ?

[Copilot]

Pull request overview

This PR fixes code generation issues when DBC files contain duplicate signal names by generating parameterized tuple enum variants instead of duplicate unit variants. When multiple signals have the same description (e.g., "reserved", "unused"), the code now generates a single tuple variant like Reserved(i8) that can hold the actual signal value, eliminating compilation errors from duplicate enum variant names.

Changes:

• Implemented duplicate detection and tuple variant generation for enum values with identical names
• Fixed signed integer type usage for signals with negative values
• Refactored multiplex indicator handling to use imported variants and matches! macro

Reviewed changes

Copilot reviewed 11 out of 11 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
tests/snapshots.rs	Removed failing tests from BAD_TESTS list; added manual test function for debugging
tests-snapshots/dbc-cantools/vehicle.snap.stderr	Removed compilation errors showing the vehicle.snap.rs file now compiles successfully
tests-snapshots/dbc-cantools/vehicle.snap.rs	Updated generated code with tuple variants for duplicate "Unused" names
tests-snapshots/dbc-cantools/issue_199_extended.snap.stderr	Removed compilation errors for duplicate "X" variants
tests-snapshots/dbc-cantools/issue_199_extended.snap.rs	Updated generated code with tuple variants for duplicate "X" names
tests-snapshots/dbc-cantools/issue_199.snap.stderr	Removed compilation errors for duplicate "X" variants
tests-snapshots/dbc-cantools/issue_199.snap.rs	Updated generated code with tuple variants for duplicate "X" names
tests-snapshots/dbc-cantools/choices.snap.stderr	Removed compilation errors for duplicate enum variants and type mismatches
tests-snapshots/dbc-cantools/choices.snap.rs	Updated generated code with i8 type for signed signals and tuple variants for duplicates
src/lib.rs	Implemented core logic for duplicate detection, tuple variant generation, and improved multiplex handling
justfile	Added test-manual command for running single file debugging tests

---

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Codecov Report

❌ Patch coverage is 87.37864% with 13 lines in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
src/lib.rs	87.37%	0 Missing and 13 partials ⚠️

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[rnd-ash]

Hey @nyurik ...

I'm trying to test it on the bug reported DBC, but it appears something broke since i last tried this with the DBC parsing

build.rs

let dbc_path = "bug_showcase.dbc";
    let dbc_file_contents = std::fs::read_to_string(dbc_path).unwrap();
    println!("cargo:rerun-if-changed={}", dbc_path);
    File::create("src/can/bug_showcase.rs").unwrap();
    let mut out =
        std::io::BufWriter::new(std::fs::File::create("src/can/bug_showcase.rs").unwrap());

    let config = dbc_codegen::Config::builder()
        .dbc_name("bug_showcase.dbc")
        .dbc_content(&dbc_file_contents)
        .debug_prints(true)
        .build();

    if let Err(e) = dbc_codegen::codegen(config, &mut out) {
        panic!("Error parsing: {e}");
    }

  --- stdout
  cargo:rerun-if-changed=bug_showcase.dbc

  --- stderr

  thread 'main' panicked at build.rs:25:9:
  Error parsing: Could not parse dbc file: Pest(
      Error {
          variant: ParsingError {
              positives: [
                  EOI,
                  env_var,
                  msg_var,
                  version,
                  new_symbols,
                  bit_timing,
                  nodes,
                  comment,
                  attr_def,
                  attr_value,
                  value_table_def,
                  value_table,
                  signal_group,
                  signal_value_type,
                  message_transmitter,
                  ba_def_rel,
                  ba_rel,
                  ba_def_def_rel,
                  ba_def_def,
                  sg_mul_val,
                  env_var_data,
              ],
              negatives: [],
          },
          location: Pos(
              86,
          ),
          line_col: Pos(
              (
                  11,
                  1,
              ),
          ),
          inner: ErrorInner {
              path: None,
              line: "SG_ Test_input_Mux M : 56|4@1+ (1,0) [0|0] \"\" Vector__XXX",
              continued_line: None,
              parse_attempts: None,
          },
      },
  )
  note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace

[nyurik]

@rnd-ash I have switched to the pest-based parser, which gets verified much more extensively than before - it is able to parse every single test case including opendbc files. Are you certain your file uses correct .dbc grammar?

[rnd-ash]

@rnd-ash I have switched to the pest-based parser, which gets verified much more extensively than before - it is able to parse every single test case including opendbc files. Are you certain your file uses correct .dbc grammar?

These DBCs are generated by PCAN tools, so I would have thought they were using correct grammar as well...

[nyurik]

interesting, thx. AI suggested a minor fix to the pest grammar - making spaces in some cases optional. I will make a new release shortly

[tegimeki]

Looks good and I think you addressed @rnd-ash's issue