lcov

LCOV tracefile parser/merger/filter in pure Rust.

[LCOV] is a graphical front-end for coverage testing tool [gcov]. It collects gcov data for multiple source files and stores them into the file called as "tracefile".

The purpose of this crate is to operate the LCOV tracefile faster than the original LCOV Perl implementation.

Usage

Add this to your Cargo.toml:

toml [dependencies] lcov = "0.8.0"

Performance

See the README of lcov-util.

Data structure

In this crate, the data structure corresponding to each line of the LCOV tracefile is called "LCOV record" and is represented as [Record]. Each line of the LCOV tracefile is composed of a string representing a kind of the record, a colon, a comma-separated field list:

lcov <KIND>:<field#0>,<field#1>,...<field#N>

LCOV record kind is represented as a variant of [Record] or [RecordKind]. Each fields of an LCOV record are represented as fields of a struct-like variant of [Record].

For details of the LCOV tracefile syntax, see the manpage of geninfo.

Examples

Parsing an LCOV tracefile:

```rust use lcov::{Record, RecordKind, Reader};

// Reader is an iterator that iterates over Result<lcov::Record, E> read from the input buffer. let mut reader = Reader::open_file("tests/fixtures/report.info")?;

// Collect the read records into a vector. let records = reader.collect::, >>()?; asserteq!(records[0], Record::TestName { name: "".into() }); assert_eq!(records[1].kind(), RecordKind::SourceFile);

// Outputs the read records in LCOV tracefile format. for record in records { println!("{}", record); } ```

Creating an LCOV report from String:

```rust use lcov::{Reader, Record};

let input = "\ TN:testname SF:/path/to/source/file.rs DA:1,2 DA:3,0 DA:5,6 LF:3 LH:2 endof_record ";

// &[u8] implements BufRead, so you can pass it as an argument to Reader::new. let mut reader = Reader::new(input.as_bytes());

let records = reader.collect::, >>()?; asserteq!(records[0], Record::TestName { name: "testname".into() }); asserteq!(records[1], Record::SourceFile { path: "/path/to/source/file.rs".into() });

// Creates an String in tracefile format. In this example, it is the same as input. let output = records.intoiter().map(|rec| format!("{}\n", rec)).collect::(); asserteq!(input, output); ```

Merging tracefiles:

```rust use lcov::{Record, RecordKind, Report};

// Creates an empty Report. let mut report = Report::new();

// Merges a first file. report.merge(Report::from_file("tests/fixtures/report.init.info")?)?;

// Merges a second file. report.merge(Report::from_file("tests/fixtures/report.run.info")?)?;

// Outputs the merge result in LCOV tracefile format. for record in report.into_records() { println!("{}", record); } ```

Minimum supported Rust version (MSRV)

The minimum supported Rust version is Rust 1.56.1. At least the last 3 versions of stable Rust are supported at any given time.

While a crate is pre-release status (0.x.x) it may have its MSRV bumped in a patch release. Once a crate has reached 1.x, any MSRV bump will be accompanied with a new minor version.

License

This project is licensed under either of

• Apache License, Version 2.0, (LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0)
• MIT license (LICENSE-MIT or http://opensource.org/licenses/MIT)

at your option.

Contribution

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in lcov by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.