feat: make pixelmatch options configurable

README.md

@@ -118,6 +118,9 @@ Currently supported values in the custom config file:
 - FAILURE_THRESHOLD: must be between 0 and 1, default to 0
 - RETRY_OPTIONS: see [retry options](https://www.npmjs.com/package/cypress-recurse#options)
 - FAIL_ON_MISSING_BASELINE: a boolean to determine whether to fail a test if its baseline doesn't exist, default to false
+- COMPARISON_OPTIONS: custom options passed to pixelmatch, see [pixelmatch options](https://github.com/mapbox/pixelmatch#api), default to `{ threshold: 0.1 }`. Please note that the `COMPARISON_OPTIONS.threshold` is different from the `FAILURE_THRESHOLD` above:
+  - `COMPARISON_OPTIONS.threshold`: is the failure threshold for every pixel comparision
+  - `FAILURE_THRESHOLD`: is the failure threshold for the whole comparision
 
 > **Note**: In order to make this custom config values effective, remember to return `getCompareSnapshotsPlugin` instance inside function `setupNodeEvents`:
 

src/config.js

@@ -13,7 +13,8 @@ const DEFAULT_CONFIG = {
   ROOT_DIR: '',
   FAILURE_THRESHOLD: 0,
   RETRY_OPTIONS: {},
-  FAIL_ON_MISSING_BASELINE: false
+  FAIL_ON_MISSING_BASELINE: false,
+  COMPARISON_OPTIONS: { threshold: 0.1 }
 }
 
 export const userConfig = { ...DEFAULT_CONFIG, ...getUserConfigFile() }

src/plugin.js

@@ -93,7 +93,7 @@ const getStatsComparisonAndPopulateDiffIfAny = async (args) => {
     diff.data,
     diff.width,
     diff.height,
-    { threshold: 0.1 }
+    userConfig.COMPARISON_OPTIONS
   )
 
   const percentage = (pixelMismatchResult / diff.width / diff.height) ** 0.5