Merge pull request #1583 from square/jw/malformed-resolve

Throw nice message when resolved URL is malformed.

retrofit/src/main/java/retrofit2/RequestBuilder.java

@@ -141,6 +141,10 @@ final class RequestBuilder {
     if (relativeUrl != null) {
       // Do a one-time combination of the built relative URL and the base URL.
       urlBuilder = baseUrl.newBuilder(relativeUrl);
+      if (urlBuilder == null) {
+        throw new IllegalArgumentException(
+            "Malformed URL. Base: " + baseUrl + ", Relative: " + relativeUrl);
+      }
       relativeUrl = null;
     }
 
@@ -175,6 +179,10 @@ final class RequestBuilder {
     } else {
       // No query parameters triggered builder creation, just combine the relative URL and base URL.
       url = baseUrl.resolve(relativeUrl);
+      if (url == null) {
+        throw new IllegalArgumentException(
+            "Malformed URL. Base: " + baseUrl + ", Relative: " + relativeUrl);
+      }
     }
 
     RequestBody body = this.body;

retrofit/src/test/java/retrofit2/RequestBuilderTest.java

@@ -1885,6 +1885,38 @@ public final class RequestBuilderTest {
     assertThat(request.body().contentType().toString()).isEqualTo("text/not-plain");
   }
 
+  @Test public void malformedAnnotationRelativeUrlThrows() {
+    class Example {
+      @GET("ftp://example.org")
+      Call<ResponseBody> get() {
+        return null;
+      }
+    }
+    try {
+      buildRequest(Example.class);
+      fail();
+    } catch (IllegalArgumentException e) {
+      assertThat(e).hasMessage(
+          "Malformed URL. Base: http://example.com/, Relative: ftp://example.org");
+    }
+  }
+
+  @Test public void malformedParameterRelativeUrlThrows() {
+    class Example {
+      @GET
+      Call<ResponseBody> get(@Url String relativeUrl) {
+        return null;
+      }
+    }
+    try {
+      buildRequest(Example.class, "ftp://example.org");
+      fail();
+    } catch (IllegalArgumentException e) {
+      assertThat(e).hasMessage(
+          "Malformed URL. Base: http://example.com/, Relative: ftp://example.org");
+    }
+  }
+
   private static void assertBody(RequestBody body, String expected) {
     assertThat(body).isNotNull();
     Buffer buffer = new Buffer();