feat(objectionary#488): handle all opcodes up to 53 instruction

src/it/custom-transformations/src/main/java/org/eolang/jeo/Bar.java

@@ -7,4 +7,9 @@ public int foo(int x) {
         }
         return 2;
     }
+
+    public void sipush() {
+        short s = 256;
+        System.out.println(s);
+    }
 }

src/it/spring-fat/pom.xml

@@ -90,7 +90,7 @@ SOFTWARE.
              support many java features. We need to implement them and enable
              the test.
           -->
-          <disabled>true</disabled>
+          <disabled>false</disabled>
         </configuration>
         <executions>
           <execution>

src/main/java/org/eolang/jeo/representation/bytecode/BytecodeInstructionEntry.java

@@ -225,6 +225,13 @@ private enum Instruction {
             visitor.visitIntInsn(Opcodes.BIPUSH, (int) arguments.get(0))
         ),
 
+        /**
+         * Push a short onto the stack as an integer value.
+         */
+        SIPUSH(Opcodes.SIPUSH, (visitor, arguments) ->
+            visitor.visitIntInsn(Opcodes.SIPUSH, (int) arguments.get(0))
+        ),
+
         /**
          * Push a constant #index from a constant pool onto the stack.
          */

src/test/java/org/eolang/jeo/representation/bytecode/BytecodeClassTest.java

@@ -193,4 +193,17 @@ void failsBecauseBytecodeIsBroken() {
             "We expect an exception here because the bytecode is broken"
         );
     }
+
+    @Test
+    void returnsShortValue() {
+        Assertions.assertDoesNotThrow(
+            () -> new BytecodeClass("ShortValue")
+                .withMethod("j$foo", "()S", Opcodes.ACC_PUBLIC)
+                .opcode(Opcodes.SIPUSH, 256)
+                .opcode(Opcodes.IRETURN)
+                .up()
+                .bytecode(),
+            "We expect no exception here because all instructions are valid"
+        );
+    }
 }