Add severity input (#16)

Co-authored-by: Joakim Sørensen <hi@ludeeus.dev>

README.md

@@ -5,7 +5,7 @@ _GitHub action for ShellCheck._
 ## Example
 
 ```yaml
-on: 
+on:
   push:
     branch:
       - master
@@ -57,3 +57,17 @@ example:
 ```
 
 This will skip `sample/directory/with/files/toignore/test.sh`
+
+## Minimum severity of errors to consider (error, warning, info, style)
+
+You can use the `severity` input to not fail until specified severity is met, for example fail only if there are errors in scripts but ignore styling, info and warnings.
+
+example:
+
+```yaml
+    ...
+    - name: Run ShellCheck
+      uses: ludeeus/action-shellcheck@master
+      with:
+        severity: error
+```

action.yaml

@@ -6,9 +6,13 @@ inputs:
     description: 'Paths to ignore when running ShellCheck'
     required: false
     default: ''
-runs: 
+  severity:
+    description: 'Minimum severity of errors to consider. Options: [error, warning, info, style]'
+    required: false
+    default: ''
+runs:
   using: 'docker'
   image: 'Dockerfile'
 branding:
-  icon: 'terminal'  
+  icon: 'terminal'
-  color: 'gray-dark'
+  color: 'gray-dark'

runaction.sh

@@ -66,9 +66,11 @@ then
     echo >&2 "::warning:: programs in PATH should not have a filename suffix"
 fi
 
+[[ -n "${INPUT_SEVERITY}" ]] && options+=(-S "${INPUT_SEVERITY}")
+
 for file in "${filepaths[@]}"; do
     echo "::debug:: Checking $file"
-    shellcheck "$file" || statuscode=$?
+    shellcheck "${options[@]}" "$file" || statuscode=$?
 done
 
 exit "$statuscode"