Add additional field tools to ASMAPI (#61)

Add a buildMethodCall() with the type as first param
This mimics how MethodInsnNodes are created with the opcode being fed
first.
Add findFirstFieldCall() methods to search for field calls
Add buildFieldCall() to build field calls

src/main/java/net/minecraftforge/coremod/api/ASMAPI.java

@@ -90,6 +90,24 @@ public static MethodInsnNode buildMethodCall(final String ownerName, final Strin
         return new MethodInsnNode(type.toOpcode(), ownerName, methodName, methodDescriptor, type == MethodType.INTERFACE);
     }
 
+    /**
+     * Builds a new {@link MethodInsnNode} with the given parameters. The opcode of the method call is determined by the
+     * given {@link MethodType}.
+     *
+     * @param type             The type of method call
+     * @param ownerName        The method owner (class)
+     * @param methodName       The method name
+     * @param methodDescriptor The method descriptor
+     * @return The built method call node
+     */
+    public static MethodInsnNode buildMethodCall(final MethodType type, final String ownerName, final String methodName, final String methodDescriptor) {
+        return new MethodInsnNode(type.toOpcode(), ownerName, methodName, methodDescriptor, type == MethodType.INTERFACE);
+    }
+
+    public static FieldInsnNode buildFieldCall(final int opcode, final String owner, final String name, final String desc) {
+        return new FieldInsnNode(opcode, owner, name, desc);
+    }
+
     /**
      * Signifies the type of number constant for a {@link NumberType}.
      */
@@ -383,6 +401,70 @@ public static MethodInsnNode findFirstMethodCallBefore(MethodNode method, Method
         return null;
     }
 
+    /**
+     * Finds the first method call in the given method matching the given type, owner, name and descriptor.
+     *
+     * @param method     the method to search in
+     * @param opcode     the opcode of field call to search for
+     * @param owner      the method call's owner to search for
+     * @param name       the method call's name
+     * @param descriptor the method call's descriptor
+     * @return the found method call node or null if none matched
+     */
+    public static @Nullable FieldInsnNode findFirstFieldCall(MethodNode method, int opcode, String owner, String name, String descriptor) {
+        return findFirstFieldCallAfter(method, opcode, owner, name, descriptor, 0);
+    }
+
+    /**
+     * Finds the first method call in the given method matching the given type, owner, name and descriptor after the
+     * instruction given index.
+     *
+     * @param method     the method to search in
+     * @param opcode     the opcode of field call to search for
+     * @param owner      the method call's owner to search for
+     * @param name       the method call's name
+     * @param descriptor the method call's descriptor
+     * @param startIndex the index after which to start searching (inclusive)
+     * @return the found method call node, null if none matched after the given index
+     */
+    public static @Nullable FieldInsnNode findFirstFieldCallAfter(MethodNode method, int opcode, String owner, String name, String descriptor, int startIndex) {
+        for (int i = Math.max(0, startIndex); i < method.instructions.size(); i++) {
+            if (method.instructions.get(i) instanceof FieldInsnNode insn
+                    && insn.getOpcode() == opcode
+                    && insn.owner.equals(owner)
+                    && insn.name.equals(name)
+                    && insn.desc.equals(descriptor)) {
+                return insn;
+            }
+        }
+        return null;
+    }
+
+    /**
+     * Finds the first method call in the given method matching the given type, owner, name and descriptor before the
+     * given index in reverse search.
+     *
+     * @param method     the method to search in
+     * @param opcode     the opcode of field call to search for
+     * @param owner      the method call's owner to search for
+     * @param name       the method call's name
+     * @param descriptor the method call's descriptor
+     * @param startIndex the index at which to start searching (inclusive)
+     * @return the found method call node or null if none matched before the given startIndex
+     */
+    public static @Nullable FieldInsnNode findFirstFieldCallBefore(MethodNode method, int opcode, String owner, String name, String descriptor, int startIndex) {
+        for (int i = Math.min(method.instructions.size() - 1, startIndex); i >= 0; i--) {
+            if (method.instructions.get(i) instanceof FieldInsnNode insn
+                    && insn.getOpcode() == opcode
+                    && insn.owner.equals(owner)
+                    && insn.name.equals(name)
+                    && insn.desc.equals(descriptor)) {
+                return insn;
+            }
+        }
+        return null;
+    }
+
     /**
      * Inserts/replaces a list after/before first {@link MethodInsnNode} that matches the parameters of these functions
      * in the method provided. Only the first node matching is targeted, all other matches are ignored.