diff --git a/proxy/delete_test.go b/proxy/delete_test.go
index a88fc1cd3..bd7ef8a34 100644
--- a/proxy/delete_test.go
+++ b/proxy/delete_test.go
@@ -4,6 +4,7 @@
 package proxy
 
 import (
+	"fmt"
 	"net/http"
 
 	"testing"
@@ -55,15 +56,16 @@ func Test_DeleteFunction_Not2xxAnd404(t *testing.T) {
 	}
 }
 
-func Test_DeleteFunction_BadURL(t *testing.T) {
+func Test_DeleteFunction_MissingURLPrefix(t *testing.T) {
 	url := "127.0.0.1:8080"
 
 	stdout := test.CaptureStdout(func() {
 		DeleteFunction(url, "function-to-delete")
 	})
 
-	r := regexp.MustCompile(`(?m:first path segment in URL cannot contain colon)`)
+	expectedErrMsg := "first path segment in URL cannot contain colon"
+	r := regexp.MustCompile(fmt.Sprintf("(?m:%s)", expectedErrMsg))
 	if !r.MatchString(stdout) {
-		t.Fatalf("Output not matched: %s", stdout)
+		t.Fatalf("Want: %s\nGot: %s", expectedErrMsg, stdout)
 	}
 }
diff --git a/proxy/deploy_test.go b/proxy/deploy_test.go
index 62b135841..d6e6d3446 100644
--- a/proxy/deploy_test.go
+++ b/proxy/deploy_test.go
@@ -4,6 +4,7 @@
 package proxy
 
 import (
+	"fmt"
 	"net/http"
 
 	"testing"
@@ -75,7 +76,7 @@ func Test_DeployFunction_Not2xx(t *testing.T) {
 	}
 }
 
-func Test_DeployFunction_BadURL(t *testing.T) {
+func Test_DeployFunction_MissingURLPrefix(t *testing.T) {
 	url := "127.0.0.1:8080"
 
 	stdout := test.CaptureStdout(func() {
@@ -95,8 +96,9 @@ func Test_DeployFunction_BadURL(t *testing.T) {
 		)
 	})
 
-	r := regexp.MustCompile(`(?m:first path segment in URL cannot contain colon)`)
+	expectedErrMsg := "first path segment in URL cannot contain colon"
+	r := regexp.MustCompile(fmt.Sprintf("(?m:%s)", expectedErrMsg))
 	if !r.MatchString(stdout) {
-		t.Fatalf("Output not matched: %s", stdout)
+		t.Fatalf("Want: %s\nGot: %s", expectedErrMsg, stdout)
 	}
 }
diff --git a/proxy/invoke_test.go b/proxy/invoke_test.go
index b76be1865..211e75029 100644
--- a/proxy/invoke_test.go
+++ b/proxy/invoke_test.go
@@ -4,6 +4,7 @@
 package proxy
 
 import (
+	"fmt"
 	"net/http"
 
 	"testing"
@@ -54,7 +55,7 @@ func Test_InvokeFunction_Not2xx(t *testing.T) {
 	}
 }
 
-func Test_InvokeFunction_BadURL(t *testing.T) {
+func Test_InvokeFunction_MissingURLPrefix(t *testing.T) {
 
 	bytesIn := []byte("test data")
 	_, err := InvokeFunction(
@@ -69,8 +70,9 @@ func Test_InvokeFunction_BadURL(t *testing.T) {
 		t.Fatalf("Error was not returned")
 	}
 
-	r := regexp.MustCompile(`(?m:cannot connect to OpenFaaS on URL: )`)
+	expectedErrMsg := "cannot connect to OpenFaaS on URL:"
+	r := regexp.MustCompile(fmt.Sprintf("(?m:%s)", expectedErrMsg))
 	if !r.MatchString(err.Error()) {
-		t.Fatalf("Error not matched: %s", err)
+		t.Fatalf("Want: %s\nGot: %s", expectedErrMsg, err.Error())
 	}
 }
diff --git a/proxy/list_test.go b/proxy/list_test.go
index bb3907b4e..5405d0a3e 100644
--- a/proxy/list_test.go
+++ b/proxy/list_test.go
@@ -4,6 +4,7 @@
 package proxy
 
 import (
+	"fmt"
 	"net/http"
 	"regexp"
 
@@ -49,16 +50,17 @@ func Test_ListFunctions_Not200(t *testing.T) {
 	}
 }
 
-func Test_ListFunctions_BadURL(t *testing.T) {
+func Test_ListFunctions_MissingURLPrefix(t *testing.T) {
 	_, err := ListFunctions("127.0.0.1:8080")
 
 	if err == nil {
 		t.Fatalf("Error was not returned")
 	}
 
-	r := regexp.MustCompile(`(?m:cannot connect to OpenFaaS on URL: )`)
+	expectedErrMsg := "cannot connect to OpenFaaS on URL:"
+	r := regexp.MustCompile(fmt.Sprintf("(?m:%s)", expectedErrMsg))
 	if !r.MatchString(err.Error()) {
-		t.Fatalf("Error not matched: %s", err)
+		t.Fatalf("Want: %s\nGot: %s", expectedErrMsg, err.Error())
 	}
 }