From 520339da300b290b2791ea3c668aac682dcd9e64 Mon Sep 17 00:00:00 2001
From: Rafael Winterhalter <rafael.wth@gmail.com>
Date: Tue, 27 Jul 2021 20:05:33 +0200
Subject: [PATCH] Add specific exception type to indicate unresolved type to
 allow easier catching of specific errors.

---
 .../java/net/bytebuddy/pool/TypePool.java     | 38 ++++++++++++++++++-
 .../pool/TypePoolResolutionTest.java          | 12 ++++--
 2 files changed, 45 insertions(+), 5 deletions(-)

diff --git a/byte-buddy-dep/src/main/java/net/bytebuddy/pool/TypePool.java b/byte-buddy-dep/src/main/java/net/bytebuddy/pool/TypePool.java
index 85eadb16c40..652edb3406e 100644
--- a/byte-buddy-dep/src/main/java/net/bytebuddy/pool/TypePool.java
+++ b/byte-buddy-dep/src/main/java/net/bytebuddy/pool/TypePool.java
@@ -89,6 +89,7 @@ interface Resolution {
          * of the returned type description.
          *
          * @return The type description that is represented by this resolution.
+         * @throws NoSuchTypeException If this resolution is unresolved.
          */
         TypeDescription resolve();
 
@@ -158,7 +159,42 @@ public boolean isResolved() {
              * {@inheritDoc}
              */
             public TypeDescription resolve() {
-                throw new IllegalStateException("Cannot resolve type description for " + name);
+                throw new NoSuchTypeException(name);
+            }
+        }
+
+        /**
+         * An exception that indicates that a {@link TypePool} could not resolve a {@link TypeDescription} for a given name.
+         */
+        class NoSuchTypeException extends IllegalStateException {
+
+            /**
+             * The serial version UID.
+             */
+            private static final long serialVersionUID = 1L;
+
+            /**
+             * The name of the type that could not be resolved.
+             */
+            private final String name;
+
+            /**
+             * Creates a new exception to indicate an unresolved type.
+             *
+             * @param name The name of the type that could not be resolved.
+             */
+            public NoSuchTypeException(String name) {
+                super("Cannot resolve type description for " + name);
+                this.name = name;
+            }
+
+            /**
+             * Returns the name of the type that could not be resolved.
+             *
+             * @return The name of the type that could not be resolved.
+             */
+            public String getName() {
+                return name;
             }
         }
     }
diff --git a/byte-buddy-dep/src/test/java/net/bytebuddy/pool/TypePoolResolutionTest.java b/byte-buddy-dep/src/test/java/net/bytebuddy/pool/TypePoolResolutionTest.java
index b4708b8acb9..f3afffc9b65 100644
--- a/byte-buddy-dep/src/test/java/net/bytebuddy/pool/TypePoolResolutionTest.java
+++ b/byte-buddy-dep/src/test/java/net/bytebuddy/pool/TypePoolResolutionTest.java
@@ -3,10 +3,10 @@
 import net.bytebuddy.description.type.TypeDescription;
 import org.junit.Test;
 
+import static junit.framework.TestCase.fail;
 import static org.hamcrest.CoreMatchers.is;
 import static org.hamcrest.CoreMatchers.not;
 import static org.hamcrest.MatcherAssert.assertThat;
-import static org.junit.Assert.fail;
 import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.when;
 
@@ -21,11 +21,15 @@ public void testSimpleResolution() throws Exception {
         assertThat(new TypePool.Resolution.Simple(typeDescription).resolve(), is(typeDescription));
     }
 
-    @Test(expected = IllegalStateException.class)
+    @Test
     public void testIllegalResolution() throws Exception {
         assertThat(new TypePool.Resolution.Illegal(FOO).isResolved(), is(false));
-        new TypePool.Resolution.Illegal(FOO).resolve();
-        fail();
+        try {  
+            new TypePool.Resolution.Illegal(FOO).resolve();
+            fail();
+        } catch (TypePool.Resolution.NoSuchTypeException exception) {
+            assertThat(exception.getName(), is(FOO));
+        }
     }
 
     @Test