handle missing checklist panic (#28)

pkg/checkmate/action.go

@@ -37,7 +37,7 @@ func Run(ctx context.Context, cfg *Config, action *githubactions.Action, gh *git
 
 		if comment != "" {
 			action.Infof("Comment checklist %s", comment)
-			checklists = Parse(comment)
+			checklists = Parse(action, comment)
 		}
 	}
 
@@ -48,7 +48,7 @@ func Run(ctx context.Context, cfg *Config, action *githubactions.Action, gh *git
 
 	action.Infof("PR Body: %s", descriptionPR)
 
-	checklists = append(Parse(descriptionPR), checklists...)
+	checklists = append(Parse(action, descriptionPR), checklists...)
 	return inspect(checklists, action)
 }
 

pkg/checkmate/checklist_test.go

@@ -1,9 +1,11 @@
 package checkmate
 
 import (
+	"io"
 	"testing"
 
 	"github.com/google/go-cmp/cmp"
+	"github.com/sethvargo/go-githubactions"
 	"github.com/stretchr/testify/assert"
 )
 
@@ -104,9 +106,10 @@ func TestChecklist_MarkdownSummary(t *testing.T) {
 > - [ ] Pear`,
 		},
 	}
+	action := githubactions.New(githubactions.WithWriter(io.Discard))
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
-			checklists := Parse(tt.checklistRaw)
+			checklists := Parse(action, tt.checklistRaw)
 			assert.Equal(t, len(checklists), 1)
 			c := checklists[0]
 			if got := c.MarkdownSummary(); got != tt.want {

pkg/checkmate/commenter.go

@@ -94,7 +94,7 @@ func updateComment(ctx context.Context, action *githubactions.Action, cfg Config
 		return commentBody, err
 	}
 
-	checklists := Parse(comment.GetBody())
+	checklists := Parse(action, comment.GetBody())
 	actualFilenames := sorted(lo.WithoutEmpty(lo.Map(checklists, func(item Checklist, _ int) string {
 		return item.Meta.FilenameGlob
 	})))
@@ -115,7 +115,7 @@ func updateComment(ctx context.Context, action *githubactions.Action, cfg Config
 
 	action.Infof("Adding checklists for [ %s ]", strings.Join(globAdd, " "))
 	toAdd := lo.Map(globAdd, func(key string, _ int) Checklist {
-		return Parse(checklistConfig[key].ToChecklistItemsMD(key))[0]
+		return Parse(action, checklistConfig[key].ToChecklistItemsMD(key))[0]
 	})
 
 	checklists = sortedByFilename(append(filtered, toAdd...))

pkg/checkmate/parse.go

@@ -4,6 +4,8 @@ import (
 	"regexp"
 	"sort"
 	"strings"
+
+	"github.com/sethvargo/go-githubactions"
 )
 
 type reMatch struct {
@@ -15,7 +17,7 @@ var (
 	headerRE = regexp.MustCompile(`(?im)^ {0,3}#{1,6}\s.*`)
 )
 
-func Parse(content string) (list []Checklist) {
+func Parse(action *githubactions.Action, content string) (list []Checklist) {
 	indicators := findRE(content, indicatorRE)
 	if len(indicators) == 0 {
 		return
@@ -32,10 +34,16 @@ func Parse(content string) (list []Checklist) {
 			return checklists[i].LineNumbers[0] > indLineNumber
 		})
 
+		if c >= len(checklists) {
+			action.Warningf("No checklist found for indicator at line %d", indLineNumber)
+			continue
+		}
+
+		checklistForIndicator := checklists[c]
 		list = append(list, Checklist{
-			Items:  blockToItems(checklists[c]),
+			Items:  blockToItems(checklistForIndicator),
 			Header: closestHeaderTo(headers, indLineNumber),
-			Raw:    checklists[c].Raw,
+			Raw:    checklistForIndicator.Raw,
 			Meta:   ParseIndicator(ind.Raw),
 		})
 	}

pkg/checkmate/parse_test.go

@@ -1,11 +1,13 @@
 package checkmate
 
 import (
+	"io"
 	"regexp"
 	"strings"
 	"testing"
 
 	"github.com/google/go-cmp/cmp"
+	"github.com/sethvargo/go-githubactions"
 	"github.com/stretchr/testify/assert"
 )
 
@@ -121,12 +123,19 @@ func TestParse(t *testing.T) {
 				},
 			},
 		},
+		{
+			name:     "Indicator but no checklist",
+			args:     args{content: "<!--Checkmate-->"},
+			expected: nil,
+		},
 	}
+
+	action := githubactions.New(githubactions.WithWriter(io.Discard))
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
-			actualList := Parse(tt.args.content)
-			if !cmp.Equal(actualList, tt.expected) {
-				t.Error(cmp.Diff(actualList, tt.expected))
+			actualList := Parse(action, tt.args.content)
+			if !cmp.Equal(tt.expected, actualList) {
+				t.Error(cmp.Diff(tt.expected, actualList))
 			}
 		})
 	}