Copy Truth8.assertThat overloads for Path and OptionalLong to the main Truth class.

(split off from cl/603361985 because I was waiting on fixes to a couple projects)

We'll post some migration suggestions as part of the release notes.

This is one of the remaining loose ends of #746.

RELNOTES=Added `Truth.assertThat(Path)` and `(OptionalLong)` overloads (copied from `Truth8`).
PiperOrigin-RevId: 603713061

Author: cpovirk

core/src/main/java/com/google/common/truth/Truth.java

@@ -21,11 +21,14 @@
 import com.google.common.collect.Multimap;
 import com.google.common.collect.Multiset;
 import com.google.common.collect.Table;
+import com.google.j2objc.annotations.J2ObjCIncompatible;
 import java.math.BigDecimal;
+import java.nio.file.Path;
 import java.util.Map;
 import java.util.Optional;
 import java.util.OptionalDouble;
 import java.util.OptionalInt;
+import java.util.OptionalLong;
 import java.util.stream.IntStream;
 import java.util.stream.LongStream;
 import java.util.stream.Stream;
@@ -274,6 +277,14 @@ public static OptionalIntSubject assertThat(@Nullable OptionalInt actual) {
     return assert_().that(actual);
   }
 
+  /**
+   * @since 1.4.0 (present in {@link Truth8} since before 1.0)
+   */
+  @SuppressWarnings("Java7ApiChecker") // no more dangerous than wherever the user got the Stream
+  public static OptionalLongSubject assertThat(@Nullable OptionalLong actual) {
+    return assert_().that(actual);
+  }
+
   /**
    * @since 1.4.0 (present in {@link Truth8} since before 1.0)
    */
@@ -308,6 +319,16 @@ public static LongStreamSubject assertThat(@Nullable LongStream actual) {
 
   // TODO(b/64757353): Add support for DoubleStream?
 
+  /**
+   * @since 1.4.0 (present in {@link Truth8} since before 1.0)
+   */
+  @GwtIncompatible
+  @J2ObjCIncompatible
+  @J2ktIncompatible
+  public static PathSubject assertThat(@Nullable Path actual) {
+    return assert_().that(actual);
+  }
+
   /**
    * An {@code AssertionError} that (a) always supports a cause, even under old versions of Android
    * and (b) omits "java.lang.AssertionError:" from the beginning of its toString() representation.

core/src/test/java/com/google/common/truth/TruthAssertThatTest.java

@@ -25,8 +25,6 @@
 import com.google.common.reflect.TypeToken;
 import java.lang.reflect.Method;
 import java.lang.reflect.Modifier;
-import java.nio.file.Path;
-import java.util.OptionalLong;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.JUnit4;
@@ -47,9 +45,6 @@ public void staticAssertThatMethodsMatchStandardSubjectBuilderInstanceMethods()
     ImmutableSortedSet<TypeToken<?>> verbTypes =
         FluentIterable.from(asList(StandardSubjectBuilder.class.getMethods()))
             .filter(input -> input.getName().equals("that"))
-            // TODO: b/166630734 - Remove this when we add the assertThat overloads.
-            .filter(input -> input.getParameterTypes()[0] != OptionalLong.class)
-            .filter(input -> input.getParameterTypes()[0] != Path.class)
             .transform(TruthAssertThatTest::methodToReturnTypeToken)
             .toSortedSet(Ordering.usingToString());
     ImmutableSortedSet<TypeToken<?>> truthTypes =