Add command option to specify the source files to run the coverage on (#806)

README.md

@@ -44,6 +44,7 @@ npx hardhat coverage [command-options]
 | Option <img width=200/> | Example <img width=750/>| Description <img width=1000/> |
 |--------------|------------------------------------|--------------------------------|
 | testfiles  | `--testfiles "test/registry/*.ts"` | Test file(s) to run. (Globs must be enclosed by quotes and use [globby matching patterns][38])|
+| sources | `--sources myFolder` or `--sources myFile.sol` | Path to *single* folder or file to target for coverage. Path is relative to Hardhat's `paths.sources` (usually `contracts/`) |
 | solcoverjs | `--solcoverjs ./../.solcover.js` | Relative path from working directory to config. Useful for monorepo packages that share settings. (Path must be "./" prefixed) |
 | network    | `--network development` | Use network settings defined in the Hardhat config |
 | temp[<sup>*</sup>][14]       | `--temp build`   | :warning: **Caution** :warning:  Path to a *disposable* folder to store compilation artifacts in. Useful when your test setup scripts include hard-coded paths to a build directory. [More...][14] |

plugins/hardhat.plugin.js

@@ -97,6 +97,7 @@ task("coverage", "Generates a code coverage report for tests")
   .addOptionalParam("testfiles",  ui.flags.file,       "", types.string)
   .addOptionalParam("solcoverjs", ui.flags.solcoverjs, "", types.string)
   .addOptionalParam('temp',       ui.flags.temp,       "", types.string)
+  .addOptionalParam('sources',    ui.flags.sources,    "", types.string)
   .addFlag('matrix', ui.flags.testMatrix)
   .addFlag('abi', ui.flags.abi)
   .setAction(async function(args, env){

plugins/resources/nomiclabs.utils.js

@@ -30,8 +30,14 @@ function getTestFilePaths(files){
  * @return {HardhatConfig}        updated config
  */
 function normalizeConfig(config, args={}){
+  let sources;
+
+  (args.sources)
+    ? sources = path.join(config.paths.sources, args.sources)
+    : sources = config.paths.sources;
+
   config.workingDir = config.paths.root;
-  config.contractsDir = config.paths.sources;
+  config.contractsDir = sources;
   config.testDir = config.paths.tests;
   config.artifactsDir = config.paths.artifacts;
   config.logger = config.logger ? config.logger : {log: null};

plugins/resources/plugin.utils.js

@@ -131,8 +131,18 @@ function checkContext(config, tempContractsDir, tempArtifactsDir){
 // =============================
 
 function assembleFiles(config, skipFiles=[]){
-  const targetsPath = path.join(config.contractsDir, '**', '*.{sol,vy}');
-  const targets = shell.ls(targetsPath).map(path.normalize);
+  let targets;
+  let targetsPath;
+
+  // The targets (contractsDir) could actually be a single named file (OR a folder)
+  const extName = path.extname(config.contractsDir);
+
+  if (extName.length !== 0) {
+    targets = [ path.normalize(config.contractsDir) ];
+  } else {
+    targetsPath = path.join(config.contractsDir, '**', '*.{sol,vy}');
+    targets = shell.ls(targetsPath).map(path.normalize);
+  }
 
   skipFiles = assembleSkipped(config, targets, skipFiles);
 

test/integration/projects/test-files/contracts/otherContracts/OtherContractA.sol

@@ -0,0 +1,17 @@
+pragma solidity ^0.7.0;
+
+
+contract OtherContractA {
+  uint x;
+  constructor() public {
+  }
+
+  function sendFn() public {
+    x = 5;
+  }
+
+  function callFn() public pure returns (uint){
+    uint y = 5;
+    return y;
+  }
+}

test/integration/projects/test-files/test/other_contract_a.js

@@ -0,0 +1,15 @@
+const OtherContractA = artifacts.require("OtherContractA");
+
+contract("otherContractA", function(accounts) {
+  let instance;
+
+  before(async () => instance = await OtherContractA.new())
+
+  it('sends', async function(){
+    await instance.sendFn();
+  });
+
+  it('calls', async function(){
+    await instance.callFn();
+  })
+});

test/units/hardhat/flags.js

@@ -230,5 +230,69 @@ describe('Hardhat Plugin: command line options', function() {
     const output = require(outputPath);
     assert.deepEqual(output, expected);
   })
+
+  it('--sources folder', async function() {
+
+    const taskArgs = {
+      testfiles: path.join(hardhatConfig.paths.root, 'test/other_contract_a.js'),
+      sources: 'otherContracts'
+    };
+    mock.installFullProject('test-files');
+    mock.hardhatSetupEnv(this);
+
+    await this.env.run("coverage", taskArgs);
+
+    const expected = [
+      {
+        file: mock.pathToContract(hardhatConfig, 'otherContracts/OtherContractA.sol'),
+        pct: 100
+      }
+    ];
+
+    verify.lineCoverage(expected);
+  });
+
+  it('--sources folder/', async function() {
+
+    const taskArgs = {
+      testfiles: path.join(hardhatConfig.paths.root, 'test/other_contract_a.js'),
+      sources: 'otherContracts/'
+    };
+    mock.installFullProject('test-files');
+    mock.hardhatSetupEnv(this);
+
+    await this.env.run("coverage", taskArgs);
+
+    const expected = [
+      {
+        file: mock.pathToContract(hardhatConfig, 'otherContracts/OtherContractA.sol'),
+        pct: 100
+      }
+    ];
+
+    verify.lineCoverage(expected);
+  });
+
+  it('--sources folder/filename.sol', async function() {
+
+    const taskArgs = {
+      testfiles: path.join(hardhatConfig.paths.root, 'test/other_contract_a.js'),
+      sources: 'otherContracts/OtherContractA.sol'
+    };
+    mock.installFullProject('test-files');
+    mock.hardhatSetupEnv(this);
+
+    await this.env.run("coverage", taskArgs);
+
+    const expected = [
+      {
+        file: mock.pathToContract(hardhatConfig, 'otherContracts/OtherContractA.sol'),
+        pct: 100
+      }
+    ];
+
+    verify.lineCoverage(expected);
+  });
+
 });