Merge LibMem and LibBytes

packages/contracts/test/libraries/lib_bytes.ts

@@ -17,6 +17,12 @@ chaiSetup.configure();
 const expect = chai.expect;
 const blockchainLifecycle = new BlockchainLifecycle(web3Wrapper);
 
+// BUG: Ideally we would use Buffer.from(memory).toString('hex')
+// https://github.com/Microsoft/TypeScript/issues/23155
+const toHex = (buf: Uint8Array): string => buf.reduce((a, v) => a + ('00' + v.toString(16)).slice(-2), '0x');
+
+const fromHex = (str: string): Uint8Array => Uint8Array.from(Buffer.from(str.slice(2), 'hex'));
+
 describe('LibBytes', () => {
     let libBytes: TestLibBytesContract;
     const byteArrayShorterThan32Bytes = '0x012345';
@@ -617,5 +623,170 @@ describe('LibBytes', () => {
             );
         });
     });
+
+    describe('memCopy', () => {
+        // Create memory 0x000102...FF
+        const memSize = 256;
+        const memory = new Uint8Array(memSize).map((_, i) => i);
+        const memHex = toHex(memory);
+
+        // Reference implementation to test against
+        const refMemcpy = (mem: Uint8Array, dest: number, source: number, length: number): Uint8Array =>
+            Uint8Array.from(mem).copyWithin(dest, source, source + length);
+
+        // Test vectors: destination, source, length, job description
+        type Tests = Array<[number, number, number, string]>;
+
+        const test = (tests: Tests) =>
+            tests.forEach(([dest, source, length, job]) =>
+                it(job, async () => {
+                    const expected = refMemcpy(memory, dest, source, length);
+                    const resultStr = await libBytes.testMemcpy.callAsync(
+                        memHex,
+                        new BigNumber(dest),
+                        new BigNumber(source),
+                        new BigNumber(length),
+                    );
+                    const result = fromHex(resultStr);
+                    expect(result).to.deep.equal(expected);
+                }),
+            );
+
+        test([[0, 0, 0, 'copies zero bytes with overlap']]);
+
+        describe('copies forward', () =>
+            test([
+                [128, 0, 0, 'zero bytes'],
+                [128, 0, 1, 'one byte'],
+                [128, 0, 11, 'eleven bytes'],
+                [128, 0, 31, 'thirty-one bytes'],
+                [128, 0, 32, 'one word'],
+                [128, 0, 64, 'two words'],
+                [128, 0, 96, 'three words'],
+                [128, 0, 33, 'one word and one byte'],
+                [128, 0, 72, 'two words and eight bytes'],
+                [128, 0, 100, 'three words and four bytes'],
+            ]));
+
+        describe('copies forward within one word', () =>
+            test([
+                [16, 0, 0, 'zero bytes'],
+                [16, 0, 1, 'one byte'],
+                [16, 0, 11, 'eleven bytes'],
+                [16, 0, 16, 'sixteen bytes'],
+            ]));
+
+        describe('copies forward with one byte overlap', () =>
+            test([
+                [0, 0, 1, 'one byte'],
+                [10, 0, 11, 'eleven bytes'],
+                [30, 0, 31, 'thirty-one bytes'],
+                [31, 0, 32, 'one word'],
+                [32, 0, 33, 'one word and one byte'],
+                [71, 0, 72, 'two words and eight bytes'],
+                [99, 0, 100, 'three words and four bytes'],
+            ]));
+
+        describe('copies forward with thirty-one bytes overlap', () =>
+            test([
+                [0, 0, 31, 'thirty-one bytes'],
+                [1, 0, 32, 'one word'],
+                [2, 0, 33, 'one word and one byte'],
+                [41, 0, 72, 'two words and eight bytes'],
+                [69, 0, 100, 'three words and four bytes'],
+            ]));
+
+        describe('copies forward with one word overlap', () =>
+            test([
+                [0, 0, 32, 'one word'],
+                [1, 0, 33, 'one word and one byte'],
+                [41, 0, 72, 'two words and eight bytes'],
+                [69, 0, 100, 'three words and four bytes'],
+            ]));
+
+        describe('copies forward with one word and one byte overlap', () =>
+            test([
+                [0, 0, 33, 'one word and one byte'],
+                [40, 0, 72, 'two words and eight bytes'],
+                [68, 0, 100, 'three words and four bytes'],
+            ]));
+
+        describe('copies forward with two words overlap', () =>
+            test([
+                [0, 0, 64, 'two words'],
+                [8, 0, 72, 'two words and eight bytes'],
+                [36, 0, 100, 'three words and four bytes'],
+            ]));
+
+        describe('copies forward within one word and one byte overlap', () =>
+            test([[0, 0, 1, 'one byte'], [10, 0, 11, 'eleven bytes'], [15, 0, 16, 'sixteen bytes']]));
+
+        describe('copies backward', () =>
+            test([
+                [0, 128, 0, 'zero bytes'],
+                [0, 128, 1, 'one byte'],
+                [0, 128, 11, 'eleven bytes'],
+                [0, 128, 31, 'thirty-one bytes'],
+                [0, 128, 32, 'one word'],
+                [0, 128, 64, 'two words'],
+                [0, 128, 96, 'three words'],
+                [0, 128, 33, 'one word and one byte'],
+                [0, 128, 72, 'two words and eight bytes'],
+                [0, 128, 100, 'three words and four bytes'],
+            ]));
+
+        describe('copies backward within one word', () =>
+            test([
+                [0, 16, 0, 'zero bytes'],
+                [0, 16, 1, 'one byte'],
+                [0, 16, 11, 'eleven bytes'],
+                [0, 16, 16, 'sixteen bytes'],
+            ]));
+
+        describe('copies backward with one byte overlap', () =>
+            test([
+                [0, 0, 1, 'one byte'],
+                [0, 10, 11, 'eleven bytes'],
+                [0, 30, 31, 'thirty-one bytes'],
+                [0, 31, 32, 'one word'],
+                [0, 32, 33, 'one word and one byte'],
+                [0, 71, 72, 'two words and eight bytes'],
+                [0, 99, 100, 'three words and four bytes'],
+            ]));
+
+        describe('copies backward with thirty-one bytes overlap', () =>
+            test([
+                [0, 0, 31, 'thirty-one bytes'],
+                [0, 1, 32, 'one word'],
+                [0, 2, 33, 'one word and one byte'],
+                [0, 41, 72, 'two words and eight bytes'],
+                [0, 69, 100, 'three words and four bytes'],
+            ]));
+
+        describe('copies backward with one word overlap', () =>
+            test([
+                [0, 0, 32, 'one word'],
+                [0, 1, 33, 'one word and one byte'],
+                [0, 41, 72, 'two words and eight bytes'],
+                [0, 69, 100, 'three words and four bytes'],
+            ]));
+
+        describe('copies backward with one word and one byte overlap', () =>
+            test([
+                [0, 0, 33, 'one word and one byte'],
+                [0, 40, 72, 'two words and eight bytes'],
+                [0, 68, 100, 'three words and four bytes'],
+            ]));
+
+        describe('copies backward with two words overlap', () =>
+            test([
+                [0, 0, 64, 'two words'],
+                [0, 8, 72, 'two words and eight bytes'],
+                [0, 36, 100, 'three words and four bytes'],
+            ]));
+
+        describe('copies forward within one word and one byte overlap', () =>
+            test([[0, 0, 1, 'one byte'], [0, 10, 11, 'eleven bytes'], [0, 15, 16, 'sixteen bytes']]));
+    });
 });
 // tslint:disable:max-file-line-count