Add test cases

1 files changed, 133 insertions, 17 deletions

diff --git a/packages/contracts/test/libraries/lib_mem.ts b/packages/contracts/test/libraries/lib_mem.ts
index 8658a89b0..4316bab6e 100644
--- a/packages/contracts/test/libraries/lib_mem.ts
+++ b/packages/contracts/test/libraries/lib_mem.ts
@@ -41,28 +41,144 @@ describe('LibMem', () => {
             Uint8Array.from(memory).copyWithin(dest, source, source + length);
 
         // Test vectors: destination, source, length, job description
-        const tests: Array<[number, number, number, string]> = [
+        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 testLibMem.testMemcpy.callAsync(
+                        memHex,
+                        new BigNumber(dest),
+                        new BigNumber(source),
+                        new BigNumber(length),
+                    );
+                    const result = fromHex(resultStr);
+                    expect(result).to.deep.equal(expected);
+                }),
+            );
+
+        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, 33, 'one word and one byte'],
             [128, 0, 72, 'two words and eight bytes'],
             [128, 0, 100, 'three words and four bytes'],
-        ];
-
-        // Construct test cases
-        tests.forEach(([dest, source, length, job]) =>
-            it(`copies ${job}`, async () => {
-                const expected = refMemcpy(memory, dest, source, length);
-                const resultStr = await testLibMem.testMemcpy.callAsync(
-                    memHex,
-                    new BigNumber(dest),
-                    new BigNumber(source),
-                    new BigNumber(length),
-                );
-                const result = fromHex(resultStr);
-                expect(result).to.deep.equal(expected);
-            }),
-        );
+        ]));
+
+        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, 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'],
+        ]));
+
     });
 });