feat: add support for cmake files

Co-authored-by: Sergii Baitala <sbaitala@gmail.com>

main.go

@@ -306,6 +306,11 @@ func licenseHeader(path string, tmpl *template.Template, data licenseData) ([]by
 		lic, err = executeTemplate(tmpl, data, "", "// ", "")
 	case ".ml", ".mli", ".mll", ".mly":
 		lic, err = executeTemplate(tmpl, data, "(**", "   ", "*)")
+	default:
+		// handle various cmake files
+		if base == "cmakelists.txt" || strings.HasSuffix(base, ".cmake.in") || strings.HasSuffix(base, ".cmake") {
+			lic, err = executeTemplate(tmpl, data, "", "# ", "")
+		}
 	}
 	return lic, err
 }

main_test.go

@@ -339,6 +339,16 @@ func TestLicenseHeader(t *testing.T) {
 			[]string{"f.ml", "f.mli", "f.mll", "f.mly"},
 			"(**\n   HYS\n*)\n\n",
 		},
+		{
+			[]string{"cmakelists.txt", "f.cmake", "f.cmake.in"},
+			"# HYS\n\n",
+		},
+
+		// ensure matches are case insenstive
+		{
+			[]string{"F.PY", "DoCkErFiLe"},
+			"# HYS\n\n",
+		},
 	}
 
 	for _, tt := range tests {