From fa6cb23a6cfc15e2a7d046849c39186c27414b34 Mon Sep 17 00:00:00 2001
From: scnale <sebinale@gmail.com>
Date: Tue, 27 Oct 2020 15:25:50 -0300
Subject: [PATCH] Update buidler plugin for Hardhat compilation pipeline (#540)

---
 plugins/buidler.plugin.js                     | 68 ++++++++++++++-----
 .../projects/solc-6/buidler.config.js         |  2 +-
 2 files changed, 53 insertions(+), 17 deletions(-)

diff --git a/plugins/buidler.plugin.js b/plugins/buidler.plugin.js
index 87bddbce..cb1bdfef 100644
--- a/plugins/buidler.plugin.js
+++ b/plugins/buidler.plugin.js
@@ -9,27 +9,21 @@ const path = require('path');
 const Web3 = require('web3');
 
 const { task, types } = require("@nomiclabs/buidler/config");
-const { ensurePluginLoadedWithUsePlugin } = require("@nomiclabs/buidler/plugins");
 
 const {
   TASK_TEST,
   TASK_COMPILE,
-  TASK_COMPILE_GET_COMPILER_INPUT
+  TASK_COMPILE_SOLIDITY_GET_COMPILER_INPUT,
+  TASK_COMPILE_SOLIDITY_GET_COMPILATION_JOB_FOR_FILE,
 } = require("@nomiclabs/buidler/builtin-tasks/task-names");
 
-ensurePluginLoadedWithUsePlugin();
-
 function plugin() {
 
   // UI for the task flags...
   const ui = new PluginUI();
 
-  // Unset useLiteralContent due to solc metadata size restriction
-  task(TASK_COMPILE_GET_COMPILER_INPUT).setAction(async (_, __, runSuper) => {
-    const input = await runSuper();
-    input.settings.metadata.useLiteralContent = false;
-    return input;
-  })
+  let measureCoverage = false;
+  let instrumentedSources;
 
   task("coverage", "Generates a code coverage report for tests")
 
@@ -42,6 +36,7 @@ function plugin() {
       let ui;
       let api;
       let config;
+      instrumentedSources = {};
 
       try {
         death(buidlerUtils.finish.bind(null, config, api)); // Catch interrupt signals
@@ -91,6 +86,9 @@ function plugin() {
         } = utils.assembleFiles(config, skipFiles);
 
         targets = api.instrument(targets);
+        for (const target of targets) {
+          instrumentedSources[target.canonicalPath] = target.source;
+        }
         utils.reportSkipped(config, skipped);
 
         // ==============
@@ -104,14 +102,11 @@ function plugin() {
         } = utils.getTempLocations(config);
 
         utils.setupTempFolders(config, tempContractsDir, tempArtifactsDir)
-        utils.save(targets, config.paths.sources, tempContractsDir);
-        utils.save(skipped, config.paths.sources, tempContractsDir);
 
-        config.paths.sources = tempContractsDir;
         config.paths.artifacts = tempArtifactsDir;
         config.paths.cache = buidlerUtils.tempCacheDir(config);
-        config.solc.optimizer.enabled = false;
 
+        measureCoverage = true;
         await env.run(TASK_COMPILE);
 
         await api.onCompileComplete(config);
@@ -137,14 +132,55 @@ function plugin() {
         await api.onIstanbulComplete(config);
 
     } catch(e) {
-       error = e;
+      error = e;
+    } finally {
+      measureCoverage = false;
     }
 
     await buidlerUtils.finish(config, api);
 
     if (error !== undefined ) throw error;
     if (process.exitCode > 0) throw new Error(ui.generate('tests-fail', [process.exitCode]));
-  })
+  });
+
+  task(TASK_COMPILE_SOLIDITY_GET_COMPILER_INPUT).setAction(async (_, { config }, runSuper) => {
+    const solcInput = await runSuper();
+    if (measureCoverage) {
+      // The source name here is actually the global name in the solc input,
+      // but buidler uses the fully qualified contract names.
+      for (const [sourceName, source] of Object.entries(solcInput.sources)) {
+        const absolutePath = path.join(config.paths.root, sourceName);
+        // Patch in the instrumented source code.
+        if (absolutePath in instrumentedSources) {
+          source.content = instrumentedSources[absolutePath];
+        }
+      }
+    }
+    return solcInput;
+  });
+
+  // Solidity settings are best set here instead of the TASK_COMPILE_SOLIDITY_GET_COMPILER_INPUT task.
+  task(TASK_COMPILE_SOLIDITY_GET_COMPILATION_JOB_FOR_FILE).setAction(async (_, __, runSuper) => {
+    const compilationJob = await runSuper();
+    if (measureCoverage && typeof compilationJob === "object") {
+      if (compilationJob.solidityConfig.settings === undefined) {
+        compilationJob.solidityConfig.settings = {};
+      }
+
+      const { settings } = compilationJob.solidityConfig;
+      if (settings.metadata === undefined) {
+        settings.metadata = {};
+      }
+      if (settings.optimizer === undefined) {
+        settings.optimizer = {};
+      }
+      // Unset useLiteralContent due to solc metadata size restriction
+      settings.metadata.useLiteralContent = false;
+      // Override optimizer settings for all compilers
+      settings.optimizer.enabled = false;
+    }
+    return compilationJob;
+  });
 }
 
 module.exports = plugin;
diff --git a/test/integration/projects/solc-6/buidler.config.js b/test/integration/projects/solc-6/buidler.config.js
index d7348483..3aee4562 100644
--- a/test/integration/projects/solc-6/buidler.config.js
+++ b/test/integration/projects/solc-6/buidler.config.js
@@ -4,7 +4,7 @@ usePlugin("@nomiclabs/buidler-truffle5");
 
 module.exports={
   defaultNetwork: "buidlerevm",
-  solc: {
+  solidity: {
     version: "0.6.5"
   }
 };