From 7a459c537af7c37fc8e28844bc762518ddb5a8b9 Mon Sep 17 00:00:00 2001
From: Simon Warta <simon@warta.it>
Date: Sun, 9 Aug 2020 14:35:26 +0200
Subject: [PATCH] Add omitDefault implementation

---
 packages/proto-signing/src/adr27.spec.ts   | 50 ++++++++++++++++++++++
 packages/proto-signing/src/adr27.ts        | 19 ++++++++
 packages/proto-signing/src/signing.spec.ts | 13 +++---
 packages/proto-signing/types/adr27.d.ts    |  7 +++
 4 files changed, 83 insertions(+), 6 deletions(-)
 create mode 100644 packages/proto-signing/src/adr27.spec.ts
 create mode 100644 packages/proto-signing/src/adr27.ts
 create mode 100644 packages/proto-signing/types/adr27.d.ts

diff --git a/packages/proto-signing/src/adr27.spec.ts b/packages/proto-signing/src/adr27.spec.ts
new file mode 100644
index 00000000..785cb43c
--- /dev/null
+++ b/packages/proto-signing/src/adr27.spec.ts
@@ -0,0 +1,50 @@
+import { fromHex } from "@cosmjs/encoding";
+import { parse } from "protobufjs";
+
+import { omitDefault } from "./adr27";
+
+describe("adr27", () => {
+  describe("omitDefault", () => {
+    it("works for strings", () => {
+      expect(omitDefault("abc")).toEqual("abc");
+      expect(omitDefault("")).toEqual(null);
+    });
+
+    it("works for bytes", () => {
+      expect(omitDefault(fromHex("ab"))).toEqual(fromHex("ab"));
+      expect(omitDefault(fromHex(""))).toEqual(null);
+    });
+
+    it("works for integers", () => {
+      expect(omitDefault(123)).toEqual(123);
+      expect(omitDefault(0)).toEqual(null);
+    });
+
+    it("works for floats", () => {
+      expect(omitDefault(1.234)).toEqual(1.234);
+      expect(omitDefault(0.0)).toEqual(null);
+    });
+
+    it("works for repeaded", () => {
+      expect(omitDefault(["a", "b", "c"])).toEqual(["a", "b", "c"]);
+      expect(omitDefault([])).toEqual(null);
+    });
+
+    it("works for enums", () => {
+      const proto = `
+        package blog;
+        syntax = "proto3";
+
+        enum Review {
+          UNSPECIFIED = 0;
+          ACCEPTED = 1;
+          REJECTED = 2;
+        };
+      `;
+      // eslint-disable-next-line @typescript-eslint/naming-convention
+      const Review = parse(proto).root.lookupEnum("blog.Review");
+      expect(omitDefault(Review.values["ACCEPTED"])).toEqual(Review.values["ACCEPTED"]);
+      expect(omitDefault(Review.values["UNSPECIFIED"])).toEqual(null);
+    });
+  });
+});
diff --git a/packages/proto-signing/src/adr27.ts b/packages/proto-signing/src/adr27.ts
new file mode 100644
index 00000000..22a57df9
--- /dev/null
+++ b/packages/proto-signing/src/adr27.ts
@@ -0,0 +1,19 @@
+import { isUint8Array } from "@cosmjs/utils";
+
+/**
+ * Converts default values to null in order to tell protobuf.js
+ * to not serialize them.
+ *
+ * @see https://github.com/cosmos/cosmos-sdk/pull/6979
+ */
+export function omitDefault<T>(input: T): T | null {
+  if (typeof input === "number" || typeof input === "boolean" || typeof input === "string") {
+    return input || null;
+  }
+
+  if (Array.isArray(input) || isUint8Array(input)) {
+    return input.length ? input : null;
+  }
+
+  throw new Error("Input type not supported");
+}
diff --git a/packages/proto-signing/src/signing.spec.ts b/packages/proto-signing/src/signing.spec.ts
index 31659d82..fd3f2493 100644
--- a/packages/proto-signing/src/signing.spec.ts
+++ b/packages/proto-signing/src/signing.spec.ts
@@ -2,6 +2,7 @@
 import { Bech32, fromBase64, fromHex, toHex } from "@cosmjs/encoding";
 import { Secp256k1Wallet } from "@cosmjs/launchpad";
 
+import { omitDefault } from "./adr27";
 import { cosmos } from "./generated/codecimpl";
 import { defaultRegistry } from "./msgs";
 import { Registry, TxBodyValue } from "./registry";
@@ -29,7 +30,7 @@ const faucet = {
 // simd tx bank send --sign-mode direct --chain-id simd-testing testgen cosmos1qypqxpq9qcrsszg2pvxq6rs0zqg3yyc5lzv7xu 1234567ucosm -b block
 const testVectors = [
   {
-    sequenceNumber: undefined, // Go doesn’t encode 0
+    sequenceNumber: 0,
     signedTxBytes:
       "0a580a560a142f636f736d6f732e62616e6b2e4d736753656e64123e0a140d82b1e7c96dbfa42462fe612932e6bff111d51b12140102030405060708090a0b0c0d0e0f10111213141a100a0575636f736d12073132333435363712330a2b0a230a21034f04181eeba35391b858633a765c4a0c189697b40d216354d50890d350c7029012040a020801120410c09a0c1a40692d88f681d5d69924a53668e8ecec535ca0ca170d1febfb1dd87de9959b07340427d6bba22526d6c30cc622f27dc5eb1ce04cfc0ff98716154066ec69db62e5",
     signBytes:
@@ -149,11 +150,11 @@ describe("signing demo", () => {
     await Promise.all(
       testVectors.map(async ({ sequenceNumber, signBytes, signedTxBytes }) => {
         const signDoc = SignDoc.create({
-          bodyBytes: txBodyBytes,
-          authInfoBytes: authInfoBytes,
-          chainId: chainId,
-          accountNumber: accountNumber,
-          accountSequence: sequenceNumber,
+          bodyBytes: omitDefault(txBodyBytes),
+          authInfoBytes: omitDefault(authInfoBytes),
+          chainId: omitDefault(chainId),
+          accountNumber: omitDefault(accountNumber),
+          accountSequence: omitDefault(sequenceNumber),
         });
         const signDocBytes = Uint8Array.from(SignDoc.encode(signDoc).finish());
         expect(toHex(signDocBytes)).toEqual(signBytes);
diff --git a/packages/proto-signing/types/adr27.d.ts b/packages/proto-signing/types/adr27.d.ts
new file mode 100644
index 00000000..dba1b48b
--- /dev/null
+++ b/packages/proto-signing/types/adr27.d.ts
@@ -0,0 +1,7 @@
+/**
+ * Converts default values to null in order to tell protobuf.js
+ * to not serialize them.
+ *
+ * @see https://github.com/cosmos/cosmos-sdk/pull/6979
+ */
+export declare function omitDefault<T>(input: T): T | null;