js: Add preconditions as assertions

Also add bytes() to test code for clarity
gonnavis · Aug 3, 2021 · 8fe4260 · 8fe4260
1 parent 76f8de9
commit 8fe4260
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Showing 3 changed files with 35 additions and 3 deletions.
diff --git a/js/meshopt_encoder.js b/js/meshopt_encoder.js
@@ -41,6 +41,12 @@ var MeshoptEncoder = (function() {
 		return result.buffer.slice(0, write);
 	}
 
+	function assert(cond) {
+		if (!cond) {
+			throw new Error("Assertion failed");
+		}
+	}
+
 	function reorder(indices, vertices, optf) {
 		var sbrk = instance.exports.sbrk;
 		var ip = sbrk(indices.length * 4);
@@ -119,6 +125,8 @@ var MeshoptEncoder = (function() {
 			return reorder(indices, maxindex(indices) + 1, optf);
 		},
 		encodeVertexBuffer: function(source, count, size) {
+			assert(size > 0 && size <= 256);
+			assert(size % 4 == 0);
 			var bound = instance.exports.meshopt_encodeVertexBufferBound(count, size);
 			return encode(instance.exports.meshopt_encodeVertexBuffer, bound, source, count, size);
 		},
@@ -131,12 +139,18 @@ var MeshoptEncoder = (function() {
 			return encode(instance.exports.meshopt_encodeIndexSequence, bound, index32(source), count, 4);
 		},
 		encodeFilterOct: function(source, count, stride, bits) {
+			assert(stride == 4 || stride == 8);
+			assert(bits >= 1 && bits <= 16);
 			return filter(instance.exports.meshopt_encodeFilterOct, source, count, stride, bits, 4);
 		},
 		encodeFilterQuat: function(source, count, stride, bits) {
+			assert(stride == 8);
+			assert(bits >= 4 && bits <= 16);
 			return filter(instance.exports.meshopt_encodeFilterQuat, source, count, stride, bits, 4);
 		},
 		encodeFilterExp: function(source, count, stride, bits) {
+			assert(stride > 0 && stride % 4 == 0);
+			assert(bits >= 1 && bits <= 24);
 			return filter(instance.exports.meshopt_encodeFilterExp, source, count, stride, bits, stride/4);
 		},
 	};

diff --git a/js/meshopt_encoder.module.js b/js/meshopt_encoder.module.js
@@ -41,6 +41,12 @@ var MeshoptEncoder = (function() {
 		return result.buffer.slice(0, write);
 	}
 
+	function assert(cond) {
+		if (!cond) {
+	        throw new Error("Assertion failed");
+		}
+	}
+
 	function reorder(indices, vertices, optf) {
 		var sbrk = instance.exports.sbrk;
 		var ip = sbrk(indices.length * 4);
@@ -119,6 +125,8 @@ var MeshoptEncoder = (function() {
 			return reorder(indices, maxindex(indices) + 1, optf);
 		},
 		encodeVertexBuffer: function(source, count, size) {
+			assert(size > 0 && size <= 256);
+			assert(size % 4 == 0);
 			var bound = instance.exports.meshopt_encodeVertexBufferBound(count, size);
 			return encode(instance.exports.meshopt_encodeVertexBuffer, bound, source, count, size);
 		},
@@ -131,12 +139,18 @@ var MeshoptEncoder = (function() {
 			return encode(instance.exports.meshopt_encodeIndexSequence, bound, index32(source), count, 4);
 		},
 		encodeFilterOct: function(source, count, stride, bits) {
+			assert(stride == 4 || stride == 8);
+			assert(bits >= 1 && bits <= 16);
 			return filter(instance.exports.meshopt_encodeFilterOct, source, count, stride, bits, 4);
 		},
 		encodeFilterQuat: function(source, count, stride, bits) {
+			assert(stride == 8);
+			assert(bits >= 4 && bits <= 16);
 			return filter(instance.exports.meshopt_encodeFilterQuat, source, count, stride, bits, 4);
 		},
 		encodeFilterExp: function(source, count, stride, bits) {
+			assert(stride > 0 && stride % 4 == 0);
+			assert(bits >= 1 && bits <= 24);
 			return filter(instance.exports.meshopt_encodeFilterExp, source, count, stride, bits, stride/4);
 		},
 	};

diff --git a/js/meshopt_encoder.test.js b/js/meshopt_encoder.test.js
@@ -7,6 +7,10 @@ process.on('unhandledRejection', error => {
 	process.exit(1);
 });
 
+function bytes(view) {
+	return new Uint8Array(view.buffer, view.byteOffset, view.byteLength);
+}
+
 var tests = {
 	reorderMesh: function() {
 		var indices = new Uint32Array([
@@ -129,7 +133,7 @@ var tests = {
 
 		// 4 vectors, encode each vector into 8 bytes with 12 bits of precision/component
 		var encoded = encoder.encodeFilterOct(data, 4, 8, 12);
-		assert.deepEqual(encoded, new Uint8Array(expected.buffer, expected.byteOffset, expected.byteLength));
+		assert.deepEqual(encoded, bytes(expected));
 	},
 
 	encodeFilterQuat12: function() {
@@ -149,7 +153,7 @@ var tests = {
 
 		// 4 quaternions, encode each quaternion into 8 bytes with 12 bits of precision/component
 		var encoded = encoder.encodeFilterQuat(data, 4, 8, 12);
-		assert.deepEqual(encoded, new Uint8Array(expected.buffer, expected.byteOffset, expected.byteLength));
+		assert.deepEqual(encoded, bytes(expected));
 	},
 
 	encodeFilterExp: function() {
@@ -167,7 +171,7 @@ var tests = {
 
 		// 1 vector with 3 components (12 bytes), encode each vector into 12 bytes with 15 bits of precision/component
 		var encoded = encoder.encodeFilterExp(data, 1, 12, 15);
-		assert.deepEqual(encoded, new Uint8Array(expected.buffer, expected.byteOffset, expected.byteLength));
+		assert.deepEqual(encoded, bytes(expected));
 	},
 };