swc_ecma_testing/
lib.rs

1use std::{env, fs, path::PathBuf, process::Command};
2
3use anyhow::{bail, Context, Result};
4use sha2::{Digest, Sha256};
5use testing::CARGO_TARGET_DIR;
6use tracing::debug;
7
8#[derive(Debug, Default, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
9pub struct JsExecOptions {
10    /// Cache the result of the execution.
11    ///
12    /// If `true`, the result of the execution will be cached.
13    /// Cache is not removed and it will be reused if the source code is
14    /// identical.
15    ///
16    /// Note that this cache is stored in cargo target directory and will be
17    /// removed by `cargo clean`.
18    ///
19    /// You can change the cache directory name by setting the
20    /// `SWC_ECMA_TESTING_CACHE_DIR`
21    pub cache: bool,
22
23    /// If true, `--input-type=module` will be added.
24    pub module: bool,
25
26    /// The arguments passed to the node.js process.
27    pub args: Vec<String>,
28}
29
30fn cargo_cache_root() -> PathBuf {
31    env::var("SWC_ECMA_TESTING_CACHE_DIR")
32        .map(PathBuf::from)
33        .unwrap_or_else(|_| CARGO_TARGET_DIR.clone())
34}
35
36/// Executes `js_code` and capture thw output.
37pub fn exec_node_js(js_code: &str, opts: JsExecOptions) -> Result<String> {
38    if opts.cache {
39        let hash = calc_hash(&format!("{:?}:{}", opts.args, js_code));
40        let cache_dir = cargo_cache_root().join(".swc-node-exec-cache");
41        let cache_path = cache_dir.join(format!("{hash}.stdout"));
42
43        if let Ok(s) = fs::read_to_string(&cache_path) {
44            return Ok(s);
45        }
46
47        let output = exec_node_js(
48            js_code,
49            JsExecOptions {
50                cache: false,
51                ..opts
52            },
53        )?;
54
55        fs::create_dir_all(&cache_dir).context("failed to create cache directory")?;
56
57        fs::write(&cache_path, output.as_bytes()).context("failed to write cache")?;
58
59        return Ok(output);
60    }
61
62    debug!("Executing nodejs:\n{}", js_code);
63
64    let mut c = Command::new("node");
65
66    if opts.module {
67        c.arg("--input-type=module");
68    } else {
69        c.arg("--input-type=commonjs");
70    }
71
72    c.arg("-e").arg(js_code);
73
74    for arg in opts.args {
75        c.arg(arg);
76    }
77
78    let output = c.output().context("failed to execute output of minifier")?;
79
80    if !output.status.success() {
81        bail!(
82            "failed to execute:\n{}\n{}",
83            String::from_utf8_lossy(&output.stdout),
84            String::from_utf8_lossy(&output.stderr)
85        )
86    }
87
88    String::from_utf8(output.stdout).context("output is not utf8")
89}
90
91fn calc_hash(s: &str) -> String {
92    let mut hasher = Sha256::default();
93    hasher.update(s.as_bytes());
94    let sum = hasher.finalize();
95
96    hex::encode(sum)
97}
swc_ecma_testing/lib.rs

swc_ecma_testing/
lib.rs
