denoland-deno/cli/tools/coverage.rs

// Copyright 2018-2020 the Deno authors. All rights reserved. MIT license.

use crate::colors;
use deno_core::error::AnyError;
use deno_core::serde_json;
use deno_core::serde_json::json;
use deno_core::url::Url;
use deno_runtime::inspector::InspectorSession;
use serde::Deserialize;
use serde::Serialize;
use std::fs;
use std::path::PathBuf;
use uuid::Uuid;

pub struct CoverageCollector {
  pub dir: PathBuf,
  session: Box<InspectorSession>,
}

impl CoverageCollector {
  pub fn new(dir: PathBuf, session: Box<InspectorSession>) -> Self {
    Self { dir, session }
  }

  pub async fn start_collecting(&mut self) -> Result<(), AnyError> {
    self.session.post_message("Debugger.enable", None).await?;

    self.session.post_message("Profiler.enable", None).await?;

    self
      .session
      .post_message(
        "Profiler.startPreciseCoverage",
        Some(json!({"callCount": true, "detailed": true})),
      )
      .await?;

    Ok(())
  }

  pub async fn stop_collecting(&mut self) -> Result<(), AnyError> {
    let result = self
      .session
      .post_message("Profiler.takePreciseCoverage", None)
      .await?;

    let take_coverage_result: TakePreciseCoverageResult =
      serde_json::from_value(result)?;

    fs::create_dir_all(&self.dir)?;

    let script_coverages = take_coverage_result.result;
    for script_coverage in script_coverages {
      let get_script_source_value = self
        .session
        .post_message(
          "Debugger.getScriptSource",
          Some(json!({
              "scriptId": script_coverage.script_id,
          })),
        )
        .await?;

      let get_script_source_result: GetScriptSourceResult =
        serde_json::from_value(get_script_source_value)?;

      let script_source = get_script_source_result.script_source.clone();

      let coverage = Coverage {
        script_coverage,
        script_source,
      };

      // TODO(caspervonb) Would be much better to look up the source during the reporting stage
      // instead of storing it here.
      // Long term, that's what we should be doing.
      let filename = format!("{}.json", Uuid::new_v4());
      let json = serde_json::to_string(&coverage)?;
      fs::write(self.dir.join(filename), &json)?;
    }

    self
      .session
      .post_message("Profiler.stopPreciseCoverage", None)
      .await?;

    self.session.post_message("Profiler.disable", None).await?;
    self.session.post_message("Debugger.disable", None).await?;

    Ok(())
  }
}

// TODO(caspervonb) all of these structs can and should be made private, possibly moved to
// inspector::protocol.
#[derive(Debug, Serialize, Deserialize)]
#[serde(rename_all = "camelCase")]
pub struct CoverageRange {
  pub start_offset: usize,
  pub end_offset: usize,
  pub count: usize,
}

#[derive(Debug, Serialize, Deserialize)]
#[serde(rename_all = "camelCase")]
pub struct FunctionCoverage {
  pub function_name: String,
  pub ranges: Vec<CoverageRange>,
  pub is_block_coverage: bool,
}

#[derive(Debug, Serialize, Deserialize)]
#[serde(rename_all = "camelCase")]
pub struct ScriptCoverage {
  pub script_id: String,
  pub url: String,
  pub functions: Vec<FunctionCoverage>,
}

#[derive(Debug, Serialize, Deserialize)]
#[serde(rename_all = "camelCase")]
pub struct Coverage {
  pub script_coverage: ScriptCoverage,
  pub script_source: String,
}

#[derive(Debug, Deserialize)]
#[serde(rename_all = "camelCase")]
struct TakePreciseCoverageResult {
  result: Vec<ScriptCoverage>,
}

#[derive(Debug, Deserialize)]
#[serde(rename_all = "camelCase")]
pub struct GetScriptSourceResult {
  pub script_source: String,
  pub bytecode: Option<String>,
}

pub struct PrettyCoverageReporter {
  quiet: bool,
}

// TODO(caspervonb) add support for lcov output (see geninfo(1) for format spec).
impl PrettyCoverageReporter {
  pub fn new(quiet: bool) -> PrettyCoverageReporter {
    PrettyCoverageReporter { quiet }
  }

  pub fn visit_coverage(
    &mut self,
    script_coverage: &ScriptCoverage,
    script_source: &str,
  ) {
    let lines = script_source.lines().collect::<Vec<_>>();

    let mut covered_lines: Vec<usize> = Vec::new();
    let mut uncovered_lines: Vec<usize> = Vec::new();

    let mut line_start_offset = 0;
    for (index, line) in lines.iter().enumerate() {
      let line_end_offset = line_start_offset + line.len();

      let mut count = 0;
      for function in &script_coverage.functions {
        for range in &function.ranges {
          if range.start_offset <= line_start_offset
            && range.end_offset >= line_end_offset
          {
            if range.count == 0 {
              count = 0;
              break;
            }

            count += range.count;
          }
        }

        line_start_offset = line_end_offset;
      }
      if count > 0 {
        covered_lines.push(index);
      } else {
        uncovered_lines.push(index);
      }
    }

    if !self.quiet {
      print!("cover {} ... ", script_coverage.url);

      let line_coverage_ratio = covered_lines.len() as f32 / lines.len() as f32;
      let line_coverage = format!(
        "{:.3}% ({}/{})",
        line_coverage_ratio * 100.0,
        covered_lines.len(),
        lines.len()
      );

      if line_coverage_ratio >= 0.9 {
        println!("{}", colors::green(&line_coverage));
      } else if line_coverage_ratio >= 0.75 {
        println!("{}", colors::yellow(&line_coverage));
      } else {
        println!("{}", colors::red(&line_coverage));
      }

      let mut last_line = None;
      for line_index in uncovered_lines {
        const WIDTH: usize = 4;
        const SEPERATOR: &str = "|";

        // Put a horizontal separator between disjoint runs of lines
        if let Some(last_line) = last_line {
          if last_line + 1 != line_index {
            let dash = colors::gray(&"-".repeat(WIDTH + 1));
            println!("{}{}{}", dash, colors::gray(SEPERATOR), dash);
          }
        }

        println!(
          "{:width$} {} {}",
          line_index + 1,
          colors::gray(SEPERATOR),
          colors::red(&lines[line_index]),
          width = WIDTH
        );

        last_line = Some(line_index);
      }
    }
  }
}

fn collect_coverages(dir: &PathBuf) -> Result<Vec<Coverage>, AnyError> {
  let mut coverages: Vec<Coverage> = Vec::new();

  let entries = fs::read_dir(dir)?;
  for entry in entries {
    let json = fs::read_to_string(entry.unwrap().path())?;
    let coverage: Coverage = serde_json::from_str(&json)?;

    coverages.push(coverage);
  }

  // TODO(caspervonb) drain_filter would make this cleaner, its nightly at the moment.
  if coverages.len() > 1 {
    coverages.sort_by_key(|k| k.script_coverage.url.clone());

    for i in (1..coverages.len() - 1).rev() {
      if coverages[i].script_coverage.url
        == coverages[i - 1].script_coverage.url
      {
        let current = coverages.remove(i);
        let previous = &mut coverages[i - 1];

        for function in current.script_coverage.functions {
          previous.script_coverage.functions.push(function);
        }
      }
    }
  }

  Ok(coverages)
}

fn filter_coverages(
  coverages: Vec<Coverage>,
  exclude: Vec<Url>,
) -> Vec<Coverage> {
  coverages
    .into_iter()
    .filter(|e| {
      if let Ok(url) = Url::parse(&e.script_coverage.url) {
        if url.path().ends_with("__anonymous__") {
          return false;
        }

        for module_url in &exclude {
          if &url == module_url {
            return false;
          }
        }

        if let Ok(path) = url.to_file_path() {
          for module_url in &exclude {
            if let Ok(module_path) = module_url.to_file_path() {
              if path.starts_with(module_path.parent().unwrap()) {
                return true;
              }
            }
          }
        }
      }

      false
    })
    .collect::<Vec<Coverage>>()
}

pub fn report_coverages(
  dir: &PathBuf,
  quiet: bool,
  exclude: Vec<Url>,
) -> Result<(), AnyError> {
  let coverages = collect_coverages(dir)?;
  let coverages = filter_coverages(coverages, exclude);

  let mut coverage_reporter = PrettyCoverageReporter::new(quiet);
  for coverage in coverages {
    let script_coverage = coverage.script_coverage;
    let script_source = coverage.script_source;
    coverage_reporter.visit_coverage(&script_coverage, &script_source);
  }

  Ok(())
}