Don't print empty add dep commands

PiperOrigin-RevId: 192539741

1 files changed, 8 insertions, 4 deletions

diff --git a/src/java_tools/buildjar/java/com/google/devtools/build/buildjar/javac/plugins/dependency/DependencyModule.java b/src/java_tools/buildjar/java/com/google/devtools/build/buildjar/javac/plugins/dependency/DependencyModule.java
index b317bccb3e..347f153fec 100644
--- a/src/java_tools/buildjar/java/com/google/devtools/build/buildjar/javac/plugins/dependency/DependencyModule.java
+++ b/src/java_tools/buildjar/java/com/google/devtools/build/buildjar/javac/plugins/dependency/DependencyModule.java
@@ -15,9 +15,10 @@
 package com.google.devtools.build.buildjar.javac.plugins.dependency;
 
 import static com.google.common.collect.ImmutableList.toImmutableList;
-import static java.util.stream.Collectors.joining;
+import static com.google.common.collect.ImmutableSet.toImmutableSet;
 
 import com.google.common.annotations.VisibleForTesting;
+import com.google.common.base.Joiner;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableSet;
 import com.google.common.collect.Streams;
@@ -343,15 +344,18 @@ public final class DependencyModule {
     private static class DefaultFixMessage implements FixMessage {
       @Override
       public String get(Iterable<JarOwner> missing, String recipient, DependencyModule depModule) {
-        String missingTargetsStr =
+        ImmutableSet<String> missingTargets =
             Streams.stream(missing)
                 .flatMap(owner -> owner.label().map(Stream::of).orElse(Stream.empty()))
-                .collect(joining(" "));
+                .collect(toImmutableSet());
+        if (missingTargets.isEmpty()) {
+          return "";
+        }
         return String.format(
             "%1$s ** Please add the following dependencies:%2$s \n  %3$s to %4$s \n"
                 + "%1$s ** You can use the following buildozer command:%2$s "
                 + "\nbuildozer 'add deps %3$s' %4$s \n\n",
-            "\033[35m\033[1m", "\033[0m", missingTargetsStr.toString(), recipient);
+            "\033[35m\033[1m", "\033[0m", Joiner.on(" ").join(missingTargets), recipient);
       }
     }