Including line number: Dockerfile FROM not pinned (#1258)

Co-authored-by: laurentsimon <64505099+laurentsimon@users.noreply.github.com>

checks/pinned_dependencies.go

@@ -391,14 +391,26 @@ func validateDockerfileIsPinned(pathfn string, content []byte,
 
 			// Not pinned.
 			ret = false
-			dl.Warn("dependency not pinned by hash %v: '%v'", pathfn, name)
+			dl.Warn3(&checker.LogMessage{
+				Path:    pathfn,
+				Type:    checker.FileTypeSource,
+				Offset:  child.StartLine,
+				Text:    fmt.Sprintf("dependency not pinned by hash: '%v'", name),
+				Snippet: child.Original,
+			})
 
 		// FROM name.
 		case len(valueList) == 1:
 			name := valueList[0]
 			if !regex.Match([]byte(name)) {
 				ret = false
-				dl.Warn("dependency not pinned by hash %v: '%v'", pathfn, name)
+				dl.Warn3(&checker.LogMessage{
+					Path:    pathfn,
+					Type:    checker.FileTypeSource,
+					Offset:  child.StartLine,
+					Text:    fmt.Sprintf("dependency not pinned by hash: '%v'", name),
+					Snippet: child.Original,
+				})
 			}
 
 		default:

checks/pinned_dependencies_test.go

@@ -383,6 +383,79 @@ func TestDockerfilePinning(t *testing.T) {
 	}
 }
 
+func TestDockerfilePinningFromLineNumber(t *testing.T) {
+	t.Parallel()
+	tests := []struct {
+		name     string
+		filename string
+		expected []struct {
+			snippet    string
+			lineNumber int
+		}
+	}{
+		{
+			name:     "Non-pinned dockerfile as",
+			filename: "./testdata/Dockerfile-not-pinned-as",
+			expected: []struct {
+				snippet    string
+				lineNumber int
+			}{
+				{
+					snippet:    "FROM python:3.7 as build",
+					lineNumber: 17,
+				},
+				{
+					snippet:    "FROM build",
+					lineNumber: 23,
+				},
+				{
+					snippet:    "FROM base2",
+					lineNumber: 29,
+				},
+			},
+		},
+		{
+			name:     "Non-pinned dockerfile",
+			filename: "./testdata/Dockerfile-not-pinned",
+			expected: []struct {
+				snippet    string
+				lineNumber int
+			}{
+				{
+					snippet:    "FROM python:3.7",
+					lineNumber: 17,
+				},
+			},
+		},
+	}
+	for _, tt := range tests {
+		tt := tt // Re-initializing variable so it is not changed while executing the closure below
+		t.Run(tt.name, func(t *testing.T) {
+			t.Parallel()
+			content, err := os.ReadFile(tt.filename)
+			if err != nil {
+				t.Errorf("cannot read file: %v", err)
+			}
+			dl := scut.TestDetailLogger{}
+			var pinned pinnedResult
+			_, err = validateDockerfileIsPinned(tt.filename, content, &dl, &pinned)
+			if err != nil {
+				t.Errorf("error during validateDockerfileIsPinned: %v", err)
+			}
+			for _, expectedLog := range tt.expected {
+				isExpectedLog := func(logMessage checker.LogMessage, logType checker.DetailType) bool {
+					return logMessage.Offset == expectedLog.lineNumber && logMessage.Path == tt.filename &&
+						logMessage.Snippet == expectedLog.snippet && logType == checker.DetailWarn &&
+						strings.Contains(logMessage.Text, "dependency not pinned by hash")
+				}
+				if !scut.ValidateLogMessage(isExpectedLog, &dl) {
+					t.Errorf("test failed: log message not present: %+v", tt.expected)
+				}
+			}
+		})
+	}
+}
+
 func TestDockerfilePinningWihoutHash(t *testing.T) {
 	t.Parallel()
 	tests := []struct {