circom_tester/wasm/tester.js
wasm/tester.jsRaw
1const chai = require("chai");
2const assert = chai.assert;
3
4const fs = require("fs");
5var tmp = require("tmp-promise");
6const path = require("path");
7
8const util = require("util");
9const exec = util.promisify(require("child_process").exec);
10
11const loadR1cs = require("r1csfile").load;
12const ZqField = require("ffjavascript").ZqField;
13
14module.exports = wasm_tester;
15
16async function wasm_tester(circomInput, _options) {
17
18 assert(await compiler_above_version("2.0.0"),"Wrong compiler version. Must be at least 2.0.0");
19
20 tmp.setGracefulCleanup();
21
22 const dir = await tmp.dir({prefix: "circom_", unsafeCleanup: true });
23
24 //console.log(dir.path);
25
26 const baseName = path.basename(circomInput, ".circom");
27 const options = Object.assign({}, _options);
28
29 options.wasm = true;
30
31 options.sym = true;
32 options.json = options.json || false; // costraints in json format
33 options.r1cs = true;
34 options.output = dir.path;
35
36 await compile(circomInput, options);
37
38 const utils = require("./utils");
39 const WitnessCalculator = require("./witness_calculator");
40
41 const wasm = await fs.promises.readFile(path.join(dir.path, baseName+"_js/"+ baseName + ".wasm"));
42
43 const wc = await WitnessCalculator(wasm);
44
45 return new WasmTester(dir, baseName, wc);
46}
47
48async function compile (fileName, options) {
49 var flags = "--wasm ";
50 if (options.sym) flags += "--sym ";
51 if (options.r1cs) flags += "--r1cs ";
52 if (options.json) flags += "--json ";
53 if (options.output) flags += "--output " + options.output + " ";
54
55 b = await exec("circom " + flags + fileName);
56 assert(b.stderr == "",
57 "circom compiler error \n" + b.stderr);
58}
59
60class WasmTester {
61
62 constructor(dir, baseName, witnessCalculator) {
63 this.dir=dir;
64 this.baseName = baseName;
65 this.witnessCalculator = witnessCalculator;
66 }
67
68 async release() {
69 await this.dir.cleanup();
70 }
71
72 async calculateWitness(input, sanityCheck) {
73 return await this.witnessCalculator.calculateWitness(input, sanityCheck);
74 }
75
76 async loadSymbols() {
77 if (this.symbols) return;
78 this.symbols = {};
79 const symsStr = await fs.promises.readFile(
80 path.join(this.dir.path, this.baseName + ".sym"),
81 "utf8"
82 );
83 const lines = symsStr.split("\n");
84 for (let i=0; i<lines.length; i++) {
85 const arr = lines[i].split(",");
86 if (arr.length!=4) continue;
87 this.symbols[arr[3]] = {
88 labelIdx: Number(arr[0]),
89 varIdx: Number(arr[1]),
90 componentIdx: Number(arr[2]),
91 };
92 }
93 }
94
95 async loadConstraints() {
96 const self = this;
97 if (this.constraints) return;
98 const r1cs = await loadR1cs(path.join(this.dir.path, this.baseName + ".r1cs"),true, false);
99 self.F = new ZqField(r1cs.prime);
100 self.nVars = r1cs.nVars;
101 self.constraints = r1cs.constraints;
102 }
103
104 async assertOut(actualOut, expectedOut) {
105 const self = this;
106 if (!self.symbols) await self.loadSymbols();
107
108 checkObject("main", expectedOut);
109
110 function checkObject(prefix, eOut) {
111
112 if (Array.isArray(eOut)) {
113 for (let i=0; i<eOut.length; i++) {
114 checkObject(prefix + "["+i+"]", eOut[i]);
115 }
116 } else if ((typeof eOut == "object")&&(eOut.constructor.name == "Object")) {
117 for (let k in eOut) {
118 checkObject(prefix + "."+k, eOut[k]);
119 }
120 } else {
121 if (typeof self.symbols[prefix] == "undefined") {
122 assert(false, "Output variable not defined: "+ prefix);
123 }
124 const ba = actualOut[self.symbols[prefix].varIdx].toString();
125 const be = eOut.toString();
126 assert.strictEqual(ba, be, prefix);
127 }
128 }
129 }
130
131 async getDecoratedOutput(witness) {
132 const self = this;
133 const lines = [];
134 if (!self.symbols) await self.loadSymbols();
135 for (let n in self.symbols) {
136 let v;
137 if (utils.isDefined(witness[self.symbols[n].varIdx])) {
138 v = witness[self.symbols[n].varIdx].toString();
139 } else {
140 v = "undefined";
141 }
142 lines.push(`${n} --> ${v}`);
143 }
144 return lines.join("\n");
145 }
146
147 async checkConstraints(witness) {
148 const self = this;
149 if (!self.constraints) await self.loadConstraints();
150 for (let i=0; i<self.constraints.length; i++) {
151 checkConstraint(self.constraints[i]);
152 }
153
154 function checkConstraint(constraint) {
155
156 const F = self.F;
157 const a = evalLC(constraint[0]);
158 const b = evalLC(constraint[1]);
159 const c = evalLC(constraint[2]);
160 assert (F.isZero(F.sub(F.mul(a,b), c)), "Constraint doesn't match");
161 }
162
163 function evalLC(lc) {
164 const F = self.F;
165 let v = F.zero;
166 for (let w in lc) {
167 v = F.add(
168 v,
169 F.mul( lc[w], witness[w] )
170 );
171 }
172 return v;
173 }
174 }
175
176}
177
178function version_to_list ( v ) {
179 return v.split(".").map(function(x) {
180 return parseInt(x, 10);
181 });
182}
183
184function check_versions ( v1, v2 ) {
185 //check if v1 is newer than or equal to v2
186 for (let i = 0; i < v2.length; i++) {
187 if (v1[i] > v2[i]) return true;
188 if (v1[i] < v2[i]) return false;
189 }
190 return true;
191}
192
193async function compiler_above_version(v) {
194 let output = await exec('circom --version').toString();
195 let compiler_version = version_to_list(output.slice(output.search(/\d/),-1));
196 vlist = version_to_list(v);
197 return check_versions ( compiler_version, vlist );
198}
199