Support 32+ parameter constructors in code gen (#978)

* Add MultipleMasksTest test

* Use multiple masks for constructors with more than 32 parameters

Resolves #977

* Add non-default arg to test

* Emit hex literals

* Simpler int math

* Don't allocate a mask if there's no properties

kotlin/tests/src/test/kotlin/com/squareup/moshi/kotlin/codegen/MultipleMasksTest.kt

@@ -0,0 +1,124 @@
+/*
+ * Copyright (C) 2019 Square, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.squareup.moshi.kotlin.codegen
+
+import com.squareup.moshi.JsonClass
+import com.squareup.moshi.Moshi
+import org.intellij.lang.annotations.Language
+import org.junit.Assert.assertEquals
+import org.junit.Test
+
+/**
+ * This test explicitly tests mask generation for classes with more than 32 parameters. Each mask
+ * can only indicate up to 32 parameters, so constructors with more than 32 parameters have to use
+ * multiple masks.
+ *
+ * This covers a few cases of this:
+ * - Ensuring values from json are matched to properties correctly
+ * - Some `@Transient` parameters (which participate in the constructor signature and mask indices)
+ * - This example has 3 total masks generated.
+ *
+ * Regression test for https://github.com/square/moshi/issues/977
+ */
+class MultipleMasksTest {
+  @Test fun testMultipleMasks() {
+
+    // Set some arbitrary values to make sure offsets are aligning correctly
+    @Language("JSON")
+    val json = """{"arg50":500,"arg3":34,"arg11":11,"arg65":67}"""
+
+    val instance = Moshi.Builder().build().adapter(MultipleMasks::class.java)
+        .fromJson(json)!!
+
+    assertEquals(instance.arg2, 2)
+    assertEquals(instance.arg3, 34)
+    assertEquals(instance.arg11, 11)
+    assertEquals(instance.arg49, 49)
+    assertEquals(instance.arg50, 500)
+    assertEquals(instance.arg65, 67)
+    assertEquals(instance.arg64, 64)
+  }
+}
+
+@JsonClass(generateAdapter = true)
+class MultipleMasks(
+    val arg0: Long = 0,
+    val arg1: Long = 1,
+    val arg2: Long = 2,
+    val arg3: Long = 3,
+    val arg4: Long = 4,
+    val arg5: Long = 5,
+    val arg6: Long = 6,
+    val arg7: Long = 7,
+    val arg8: Long = 8,
+    val arg9: Long = 9,
+    val arg10: Long = 10,
+    val arg11: Long,
+    val arg12: Long = 12,
+    val arg13: Long = 13,
+    val arg14: Long = 14,
+    val arg15: Long = 15,
+    val arg16: Long = 16,
+    val arg17: Long = 17,
+    val arg18: Long = 18,
+    val arg19: Long = 19,
+    val arg20: Long = 20,
+    val arg21: Long = 21,
+    val arg22: Long = 22,
+    val arg23: Long = 23,
+    val arg24: Long = 24,
+    val arg25: Long = 25,
+    val arg26: Long = 26,
+    val arg27: Long = 27,
+    val arg28: Long = 28,
+    val arg29: Long = 29,
+    val arg30: Long = 30,
+    val arg31: Long = 31,
+    val arg32: Long = 32,
+    val arg33: Long = 33,
+    val arg34: Long = 34,
+    val arg35: Long = 35,
+    val arg36: Long = 36,
+    val arg37: Long = 37,
+    val arg38: Long = 38,
+    @Transient val arg39: Long = 39,
+    val arg40: Long = 40,
+    val arg41: Long = 41,
+    val arg42: Long = 42,
+    val arg43: Long = 43,
+    val arg44: Long = 44,
+    val arg45: Long = 45,
+    val arg46: Long = 46,
+    val arg47: Long = 47,
+    val arg48: Long = 48,
+    val arg49: Long = 49,
+    val arg50: Long = 50,
+    val arg51: Long = 51,
+    val arg52: Long = 52,
+    @Transient val arg53: Long = 53,
+    val arg54: Long = 54,
+    val arg55: Long = 55,
+    val arg56: Long = 56,
+    val arg57: Long = 57,
+    val arg58: Long = 58,
+    val arg59: Long = 59,
+    val arg60: Long = 60,
+    val arg61: Long = 61,
+    val arg62: Long = 62,
+    val arg63: Long = 63,
+    val arg64: Long = 64,
+    val arg65: Long = 65
+)