Fix typo in error messages

Signed-off-by: Jean-Christophe Sirot <jean-christophe.sirot@docker.com>

Author: Jean-Christophe Sirot

render/render.go

@@ -77,11 +77,11 @@ func substituteParams(allParameters map[string]string, composeContent string) (s
 		}
 		//fail on default values enclosed within {}
 		if fail := groups["defvals"]; fail != "" {
-			return "", errors.Errorf("The default value syntax of compose file is not supported in Docker App. "+
+			return "", errors.Errorf("The default value syntax of Compose files is not supported in Docker App. "+
 				"The characters ':' and '-' are not allowed in parameter names. Invalid parameter: %s.", match[0])
 		}
 		if fail := groups["errormsg"]; fail != "" {
-			return "", errors.Errorf("The custom error message syntax of compose file is not supported in Docker App. "+
+			return "", errors.Errorf("The custom error message syntax of Compose files is not supported in Docker App. "+
 				"The characters ':' and '?' are not allowed in parameter names. Invalid parameter: %s.", match[0])
 		}
 		if skip := groups["skip"]; skip != "" {

render/render_test.go

@@ -83,7 +83,7 @@ services:
 	userParameters := map[string]string{
 		"front.port": "4242",
 	}
-	checkRenderError(t, userParameters, composeFile, "The default value syntax of compose file is not supported in Docker App. "+
+	checkRenderError(t, userParameters, composeFile, "The default value syntax of Compose files is not supported in Docker App. "+
 		"The characters ':' and '-' are not allowed in parameter names. Invalid parameter: ${front.port:-9090}.")
 
 	composeFile = `
@@ -93,7 +93,7 @@ services:
 	ports:
 		- "${front.port-9090}:80"
 	`
-	checkRenderError(t, userParameters, composeFile, "The default value syntax of compose file is not supported in Docker App. "+
+	checkRenderError(t, userParameters, composeFile, "The default value syntax of Compose files is not supported in Docker App. "+
 		"The characters ':' and '-' are not allowed in parameter names. Invalid parameter: ${front.port-9090}.")
 	composeFile = `
 version: "3.6"
@@ -102,7 +102,7 @@ services:
 	ports:
 		- "${front.port:?Error}:80"
 	`
-	checkRenderError(t, userParameters, composeFile, "The custom error message syntax of compose file is not supported in Docker App. "+
+	checkRenderError(t, userParameters, composeFile, "The custom error message syntax of Compose files is not supported in Docker App. "+
 		"The characters ':' and '?' are not allowed in parameter names. Invalid parameter: ${front.port:?Error}.")
 
 	composeFile = `
@@ -112,7 +112,7 @@ services:
 	ports:
 		- "${front.port?Error:unset variable}:80"
 	`
-	checkRenderError(t, userParameters, composeFile, "The custom error message syntax of compose file is not supported in Docker App. "+
+	checkRenderError(t, userParameters, composeFile, "The custom error message syntax of Compose files is not supported in Docker App. "+
 		"The characters ':' and '?' are not allowed in parameter names. Invalid parameter: ${front.port?Error:unset variable}.")
 
 }