Be ready for unknown browsers

browserslist · Jul 14, 2022 · 797af21 · 797af21
1 parent 2ff000a
commit 797af21
Showing 1 changed file with 10 additions and 0 deletions.
diff --git a/copy-mdn.js b/copy-mdn.js
@@ -63,6 +63,8 @@ function versionMatches(browserVersion, versionAdded, versionRemoved) {
   )
 }
 
+let unknown = {}
+
 /**
  * This function maps support data from @mdn/browser-compat-data, to caniuse's
  * format.
@@ -81,6 +83,14 @@ function bcdDataToCanIUseData(bcdData, title) {
     let browserDataRaw = supportData[browser]
     let caniuseBrowser = bcdBrowserToCanIUseBrowser(browser)
 
+    if (!agents[caniuseBrowser]) {
+      if (!unknown[caniuseBrowser]) {
+        unknown[caniuseBrowser] = true
+        console.warn(`Unknown browser ${caniuseBrowser}`)
+      }
+      return
+    }
+
     result.stats[caniuseBrowser] = {}
     // Loop through all versions for the current browser
     agents[caniuseBrowser].versions.forEach(version => {