Fix issue with querying crates.io index

The crates.io index was queried using uppercase letters for certain crates. Lookups can only be done using lowercase letters, even though a crate can have uppercase letters in its name.

PiperOrigin-RevId: 560809149
Change-Id: I1fcea808a8b7786da9084c0752f239cb36d4ce9a

java/com/google/copybara/rust/RustCratesIoVersionList.java

@@ -18,6 +18,7 @@
 
 import static com.google.common.collect.ImmutableSet.toImmutableSet;
 
+import com.google.common.base.Ascii;
 import com.google.common.collect.ImmutableSet;
 import com.google.copybara.exception.RepoException;
 import com.google.copybara.exception.ValidationException;
@@ -63,19 +64,21 @@ ImmutableSet<RustRegistryVersionObject> getVersionList() throws RepoException {
     String url = CRATES_IO_INDEX_URL;
 
     int nameLength = crateName.length();
+    String indexCrateName = Ascii.toLowerCase(crateName);
 
     if (nameLength <= 2) {
       // If the crate name's length is less than or equal to 2, then the version info is located at
       // /<name length>/<crate name>
-      url += String.format("/%d/%s", nameLength, crateName);
+      url += String.format("/%d/%s", nameLength, indexCrateName);
     } else if (nameLength == 3) {
       // If the crate name's length is equal to 3, then the version info is at:
       // /3/<first char>/<crate name>
-      url += String.format("/%d/%c/%s", nameLength, crateName.charAt(0), crateName);
+      url += String.format("/%d/%c/%s", nameLength, indexCrateName.charAt(0), indexCrateName);
     } else {
       url +=
           String.format(
-              "/%s/%s/%s", crateName.substring(0, 2), crateName.substring(2, 4), crateName);
+              "/%s/%s/%s",
+              indexCrateName.substring(0, 2), indexCrateName.substring(2, 4), indexCrateName);
     }
 
     BufferedReader reader = new BufferedReader(new StringReader(executeHTTPQuery(url)));

javatests/com/google/copybara/rust/RustCratesIoVersionListTest.java

@@ -197,4 +197,23 @@ public void testRustCrateIoVersionList_withFeatures() throws Exception {
     assertThat(resultFeatures).containsKey("example-feature");
     assertThat(resultFeatures.get("example-feature").get(0)).isEqualTo("feature2");
   }
+
+  @Test
+  public void testRustCrateIoVersionList_cratesWithUpperCaseName() throws Exception {
+    JsonObject v1 = new JsonObject();
+    v1.add("name", new JsonPrimitive("Example"));
+    v1.add("vers", new JsonPrimitive("0.1.0"));
+    String content =
+        ImmutableList.of(v1).stream().map(JsonElement::toString).collect(Collectors.joining("\n"));
+
+    setUpMockTransportForSkylarkExecutor(
+        ImmutableMap.of(
+            "https://raw.githubusercontent.com/rust-lang/crates.io-index/master/ex/am/example",
+            content));
+    // The crate name starts with an uppercase letter, but when we look up in the index, we use the
+    // lowercase spelling.
+    VersionList versionList =
+        skylark.eval("version_list", "version_list = rust.crates_io_version_list(crate='Example')");
+    assertThat(versionList.list()).containsExactlyElementsIn(ImmutableList.of("0.1.0"));
+  }
 }