From df34c1c71e74468fd67287caad2ac987176ae503 Mon Sep 17 00:00:00 2001
From: Nickolay Platonov <nickolay8@gmail.com>
Date: Wed, 1 Apr 2020 16:30:26 +0300
Subject: [PATCH] fix: Data merge concurrency limit to prevent OOM (#1293)

Fixes #1263
---
 index.js | 14 ++++++++++----
 1 file changed, 10 insertions(+), 4 deletions(-)

diff --git a/index.js b/index.js
index 6d74d0831..e2ae1c24c 100755
--- a/index.js
+++ b/index.js
@@ -408,11 +408,16 @@ class NYC {
 
   async getCoverageMapFromAllCoverageFiles (baseDirectory) {
     const map = libCoverage.createCoverageMap({})
+    const files = await this.coverageFiles(baseDirectory)
 
-    const data = await this.coverageData(baseDirectory)
-    data.forEach(report => {
-      map.merge(report)
-    })
+    await pMap(
+      files,
+      async f => {
+        const report = await this.coverageFileLoad(f, baseDirectory)
+        map.merge(report)
+      },
+      { concurrency: os.cpus().length }
+    )
 
     map.data = await this.sourceMaps.remapCoverage(map.data)
 
@@ -503,6 +508,7 @@ class NYC {
     }
   }
 
+  // TODO: Remove from nyc v16
   async coverageData (baseDirectory) {
     const files = await this.coverageFiles(baseDirectory)
     return pMap(