cargo-darwin 0.3.0

//! `cargo-darwin` is a plugin over `cargo` tool.
//!
//! Darwin mutates your code, if your code still passes check tests, then your code isn't enough tested.
//!
//! ## Usage
//! ```bash
//! cargo darwin /path/to/project/to/test
//! ```
//! Will display something like
//! ```bash
//! [Missing] : Tests pass, the mutation hasn't been caught, suspicion of missing test
//! [OK]      : Tests failed, the mutation has been caught
//! [Timeout] : Mutation introduces infinite loop, inconclusive
//! [Killed]  : Mutation introduces non buildable modification
//!   ---
//! [OK] : Mutation #0 replace - by + in function "sub" of file src\a\toto.rs at line 11:6
//! [OK] : Mutation #1 replace - by * in function "sub" of file src\a\toto.rs at line 11:6
//! [Killed] : Mutation #2 replace - by && in function "sub" of file src\a\toto.rs at line 11:6
//! [Missing] : Mutation #3 replace + by - in function "add" of file src\lib.rs at line 5:6
//! [Missing] : Mutation #4 replace + by * in function "add" of file src\lib.rs at line 5:6
//! [Missing] : Mutation #5 replace + by - in function "add" of file src\lib.rs at line 5:10
//! [Missing] : Mutation #6 replace + by * in function "add" of file src\lib.rs at line 5:10
//! ```
//!
//! ## Details
//!
//! *Darwin* walks the provided path (if none provided get the current dir).
//!
//! For each file ending by **.rs** extension, **Darwin** analyze the file and try to found mutable
//! function.
//!
//! A function is mutable if there is no `#[test]` or `#[tokio::test]` attribute over it.
//!
//! ```ignore
//! fn mutable() {}
//!
//! #[test]
//! fn non_mutable() {}
//!
//! #[tokio::test]
//! async fn non_mutable_async() {}
//! ```
//!
//! The project is in its really early stage, so the mutation are quite limited, actually just binary expressions like `a + b` or `a - b`.
//!
//! For example this mutable function
//!
//! ```
//! fn add(x: u8, y:u8) -> u8 {
//!     x + y
//! }
//! ```
//! will become
//! ```
//! fn add(x: u8, y:u8) -> u8 {
//!     x - y
//! }
//! ```
//! Then Darwin create a copy of the actual project and apply the modification on the copied file
//!
//! Once the project mutated, Darwin runs a `cargo build`, if the project compile, then the mutation is sustainable
//!
//! If so, Darwin runs the `cargo test`, There are 3 possibilities:
//! - project tests pass : the project is inefficiently tested as the mutation isn't catch
//! - tests fail : the project has at least one test which catches the mutation
//! - timeout : the mutation even if compiles, introduce a loop or something that makes the test run
//! forever
//!
//! ### Reports
//!
//! All reports can be found in the *mutation path* in a **reports** folder which.
//!
//! For example if you have run *darwin* with
//!
//! ```bash
//! cargo darwin --mutation-path /tmp/darwin /path/to/project/to/test
//! ```
//! You will get this tree
//!
//! ```bash
//! tmp/
//! ├─ darwin/
//! │  ├─ reports/
//! │  │  ├─ mutation_0.log
//! │  │  ├─ mutation_1.log
//! │  │  ├─ summary
//! │  ├─ 0/
//! │  ├─ 1/
//! ```
//!
//! #### Mutated projects
//!
//! If the `--keep` flag is defined, after tests, you can walk to generated projects
//!
//! Each one has a mutation ID and the associated mutation ID can be found in summary file
//!
//! #### Summary
//!
//! Summarize the mutation applied and the result of each.
//!
//! ```bash
//! [OK] : Mutation #0 replace - by + in function "sub" of file src\a\toto.rs at line 11:6
//! [OK] : Mutation #1 replace - by * in function "sub" of file src\a\toto.rs at line 11:6
//! [Killed] : Mutation #2 replace - by && in function "sub" of file src\a\toto.rs at line 11:6
//! [Missing] : Mutation #3 replace + by - in function "add" of file src\lib.rs at line 5:6
//! [Missing] : Mutation #4 replace + by * in function "add" of file src\lib.rs at line 5:6
//! [Missing] : Mutation #5 replace + by - in function "add" of file src\lib.rs at line 5:10
//! [Missing] : Mutation #6 replace + by * in function "add" of file src\lib.rs at line 5:10
//! ```
//!
//! For more information about the mutation, check the associated mutation_ID.log file
//!
//! #### Mutation report
//! `reports/mutation_X.log` files are the detailed view of the mutation.
//!
//! There are build with the following nomenclature
//! - Mutated file
//! - Mutation
//! - Mutation status
//! - Diff of the mutation
//! - Test or build output
//!
//! Below an example of output
//!
//! ```log
//! Mutation of file F:\Projets\Lab\Rust\darwin\playground\src\a\toto.rs
//! Mutation reason: replace - by *
//! Status : OK => Mutation Caught
//! Mutation diff:
//! @@ -8,7 +8,7 @@
//!  //
//!  fn sub(x: i8, y: i8) -> i8 {
//!      let u = 8;
//! -    x - y
//! +    x * y
//!  }
//!
//! Output:
//!
//!  #[test]
//! stderr:
//!    Compiling playground v0.1.0 (F:\Projets\Lab\Rust\darwin\tmp\1)
//!     Finished test [unoptimized + debuginfo] target(s) in 0.18s
//!      Running unittests src\lib.rs (target\debug\deps\playground-29148ab9d23d3c5d.exe)
//! error: test failed, to rerun pass `--lib`
//!
//! stdout:
//!
//! running 2 tests
//! test a::toto::test_sub ... FAILED
//! test a::toto::async_test_sub ... FAILED
//!
//! failures:
//!
//! ---- a::toto::test_sub stdout ----
//! thread 'a::toto::test_sub' panicked at src\a\toto.rs:16:5:
//! assertion `left == right` failed
//!   left: 10
//!  right: 3
//! note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
//!
//! ---- a::toto::async_test_sub stdout ----
//! thread 'a::toto::async_test_sub' panicked at src\a\toto.rs:21:5:
//! assertion `left == right` failed
//!   left: 10
//!  right: 3
//!
//!
//! failures:
//!     a::toto::async_test_sub
//!     a::toto::test_sub
//!
//! test result: FAILED. 0 passed; 2 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.00s
//! ```
//!
//! As a test has failed, the mutation has been caught, so the code is enough tested for this particular mutation
//!
use std::fs;

use clap::Parser;

use actions::{analyze, generate, reporting};
use cli::{Cli, Darwin};
use mutation::Mutation;

mod actions;
mod cli;
mod mutation;
mod report;

/// Display mutation but don't run tests
fn display_mutations(mutations: &Vec<Mutation>) -> eyre::Result<()> {
    for mutation in mutations {
        println!("{}", mutation.display(true)?)
    }
    Ok(())
}

/// Main darwin function
pub fn run() -> eyre::Result<()> {
    let cli = Cli::parse();

    let Cli::Darwin(Darwin {
        mutation_path,
        root_path,
        dry_run,
        keep,
    }) = cli;

    let root_path = fs::canonicalize(root_path)?;
    let mut mutants = analyze::analyze(&root_path)?;

    if !dry_run {
        println!("{}---", cli::help());
        generate::generate_and_verify_mutants(&mut mutants, &root_path, &mutation_path, keep)?;
        reporting::generate_reports(&mutants, &mutation_path, &root_path)?;
    } else {
        log::info!("Run Darwin in dry run");
        display_mutations(&mutants)?;
    }

    Ok(())
}