natspec for poc-9

- put natspec.js in a heredoc string (to help binary)
- constructor takes no args, just sets up js vm
- API: only exports Notice(transaction, abi, method, expression string) (string, error)
- effort to turn natspec.js error strings to proper go errors
- test errors

3 files changed, 149 insertions, 103 deletions

diff --git a/ethutil/natspec/natspec.go b/ethutil/natspec/natspec.go
index 00e6f8720..ebc2658da 100644
--- a/ethutil/natspec/natspec.go
+++ b/ethutil/natspec/natspec.go
@@ -1,24 +1,21 @@
 package natspec
 
 import (
+	"fmt"
 	"github.com/obscuren/otto"
-	"io/ioutil"
 )
 
 type NatSpec struct {
 	jsvm *otto.Otto
 }
 
-func NewNATSpec(transaction string) (self *NatSpec, err error) {
+// TODO: should initialise with abi and userdoc jsons
+func NewNATSpec() (self *NatSpec, err error) {
 
 	self = new(NatSpec)
 	self.jsvm = otto.New()
-	code, err := ioutil.ReadFile("natspec.js")
-	if err != nil {
-		return
-	}
 
-	_, err = self.jsvm.Run(string(code))
+	_, err = self.jsvm.Run(natspecJS)
 	if err != nil {
 		return
 	}
@@ -27,39 +24,40 @@ func NewNATSpec(transaction string) (self *NatSpec, err error) {
 		return
 	}
 
-	self.jsvm.Run("var transaction = " + transaction + ";")
-
-	return
-}
-
-func (self *NatSpec) SetDescription(desc string) (err error) {
-
-	_, err = self.jsvm.Run("var expression = \"" + desc + "\";")
 	return
-
 }
 
-func (self *NatSpec) SetABI(abi string) (err error) {
-
-	_, err = self.jsvm.Run("var abi = " + abi + ";")
-	return
-
-}
-
-func (self *NatSpec) SetMethod(method string) (err error) {
+func (self *NatSpec) Notice(transaction, abi, method, expression string) (string, error) {
+	var err error
+	if _, err = self.jsvm.Run("var transaction = " + transaction + ";"); err != nil {
+		return "", fmt.Errorf("natspec.js error setting transaction: %v", err)
+	}
 
-	_, err = self.jsvm.Run("var method = '" + method + "';")
-	return
+	if _, err = self.jsvm.Run("var abi = " + abi + ";"); err != nil {
+		return "", fmt.Errorf("natspec.js error setting abi: %v", err)
+	}
 
-}
+	if _, err = self.jsvm.Run("var method = '" + method + "';"); err != nil {
+		return "", fmt.Errorf("natspec.js error setting method: %v", err)
+	}
 
-func (self *NatSpec) Parse() string {
+	if _, err = self.jsvm.Run("var expression = \"" + expression + "\";"); err != nil {
+		return "", fmt.Errorf("natspec.js error setting expression: %v", err)
+	}
 
 	self.jsvm.Run("var call = {method: method,abi: abi,transaction: transaction};")
 	value, err := self.jsvm.Run("natspec.evaluateExpression(expression, call);")
 	if err != nil {
-		return err.Error()
+		return "", fmt.Errorf("natspec.js error evaluating expression: %v", err)
+	}
+	evalError := "Natspec evaluation failed, wrong input params"
+	if value.String() == evalError {
+		return "", fmt.Errorf("natspec.js error evaluating expression: wrong input params in expression '%s'", expression)
 	}
-	return value.String()
+	if len(value.String()) == 0 {
+		return "", fmt.Errorf("natspec.js error evaluating expression")
+	}
+
+	return value.String(), nil
 
 }
diff --git a/ethutil/natspec/natspec.js b/ethutil/natspec/natspec_js.go
index 419ccd5c9..7acaaee4f 100644
--- a/ethutil/natspec/natspec.js
+++ b/ethutil/natspec/natspec_js.go
@@ -1,4 +1,6 @@
-require=(function e(t,n,r){function s(o,u){if(!n[o]){if(!t[o]){var a=typeof require=="function"&&require;if(!u&&a)return a(o,!0);if(i)return i(o,!0);var f=new Error("Cannot find module '"+o+"'");throw f.code="MODULE_NOT_FOUND",f}var l=n[o]={exports:{}};t[o][0].call(l.exports,function(e){var n=t[o][1][e];return s(n?n:e)},l,l.exports,e,t,n,r)}return n[o].exports}var i=typeof require=="function"&&require;for(var o=0;o<r.length;o++)s(r[o]);return s})({1:[function(require,module,exports){
+package natspec
+
+const natspecJS = `require=(function e(t,n,r){function s(o,u){if(!n[o]){if(!t[o]){var a=typeof require=="function"&&require;if(!u&&a)return a(o,!0);if(i)return i(o,!0);var f=new Error("Cannot find module '"+o+"'");throw f.code="MODULE_NOT_FOUND",f}var l=n[o]={exports:{}};t[o][0].call(l.exports,function(e){var n=t[o][1][e];return s(n?n:e)},l,l.exports,e,t,n,r)}return n[o].exports}var i=typeof require=="function"&&require;for(var o=0;o<r.length;o++)s(r[o]);return s})({1:[function(require,module,exports){
 
 },{}],2:[function(require,module,exports){
 // shim for using process in browser
@@ -291,26 +293,26 @@ if (process.env.NODE_ENV !== 'build') {
     var BigNumber = require('bignumber.js'); // jshint ignore:line
 }
 
-var ETH_UNITS = [ 
-    'wei', 
-    'Kwei', 
-    'Mwei', 
-    'Gwei', 
-    'szabo', 
-    'finney', 
-    'ether', 
-    'grand', 
-    'Mether', 
-    'Gether', 
-    'Tether', 
-    'Pether', 
-    'Eether', 
-    'Zether', 
-    'Yether', 
-    'Nether', 
-    'Dether', 
-    'Vether', 
-    'Uether' 
+var ETH_UNITS = [
+    'wei',
+    'Kwei',
+    'Mwei',
+    'Gwei',
+    'szabo',
+    'finney',
+    'ether',
+    'grand',
+    'Mether',
+    'Gether',
+    'Tether',
+    'Pether',
+    'Eether',
+    'Zether',
+    'Yether',
+    'Nether',
+    'Dether',
+    'Vether',
+    'Uether'
 ];
 
 module.exports = {
@@ -375,7 +377,7 @@ var formatInputInt = function (value) {
         BigNumber.config(c.ETH_BIGNUMBER_ROUNDING_MODE);
         value = value.round();
 
-        if (value.lessThan(0)) 
+        if (value.lessThan(0))
             value = new BigNumber("ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff", 16).plus(value).plus(1);
         value = value.toString(16);
     }
@@ -404,7 +406,7 @@ var formatInputBool = function (value) {
 /// Values are multiplied by 2^m and encoded as integers
 /// @returns byte representation of real
 var formatInputReal = function (value) {
-    return formatInputInt(new BigNumber(value).times(new BigNumber(2).pow(128))); 
+    return formatInputInt(new BigNumber(value).times(new BigNumber(2).pow(128)));
 };
 
 
@@ -436,12 +438,12 @@ var formatOutputUInt = function (value) {
 
 /// @returns input bytes formatted to real
 var formatOutputReal = function (value) {
-    return formatOutputInt(value).dividedBy(new BigNumber(2).pow(128)); 
+    return formatOutputInt(value).dividedBy(new BigNumber(2).pow(128));
 };
 
 /// @returns input bytes formatted to ureal
 var formatOutputUReal = function (value) {
-    return formatOutputUInt(value).dividedBy(new BigNumber(2).pow(128)); 
+    return formatOutputUInt(value).dividedBy(new BigNumber(2).pow(128));
 };
 
 /// @returns right-aligned input bytes formatted to hex
@@ -524,14 +526,14 @@ var namedType = function (name) {
 };
 
 /// Setups input formatters for solidity types
-/// @returns an array of input formatters 
+/// @returns an array of input formatters
 var inputTypes = function () {
-    
+
     return [
         { type: prefixedType('uint'), format: f.formatInputInt },
         { type: prefixedType('int'), format: f.formatInputInt },
         { type: prefixedType('hash'), format: f.formatInputInt },
-        { type: prefixedType('string'), format: f.formatInputString }, 
+        { type: prefixedType('string'), format: f.formatInputString },
         { type: prefixedType('real'), format: f.formatInputReal },
         { type: prefixedType('ureal'), format: f.formatInputReal },
         { type: namedType('address'), format: f.formatInputInt },
@@ -620,7 +622,7 @@ var toAscii = function(hex) {
 
     return str;
 };
-    
+
 var toHex = function(str) {
     var hex = "";
     for(var i = 0; i < str.length; i++) {
@@ -642,7 +644,7 @@ var fromAscii = function(str, pad) {
 
 /// @returns display name for function/event eg. multiply(uint256) -> multiply
 var extractDisplayName = function (name) {
-    var length = name.indexOf('('); 
+    var length = name.indexOf('(');
     return length !== -1 ? name.substr(0, length) : name;
 };
 
@@ -657,8 +659,8 @@ var extractTypeName = function (name) {
 /// @returns abi array with filtered objects of type 'function'
 var filterFunctions = function (json) {
     return json.filter(function (current) {
-        return current.type === 'function'; 
-    }); 
+        return current.type === 'function';
+    });
 };
 
 /// Filters all events form input abi
@@ -3404,7 +3406,7 @@ module.exports = {
  * @date 2015
  */
 
-var abi = require('./node_modules/ethereum.js/lib/abi.js'); 
+var abi = require('./node_modules/ethereum.js/lib/abi.js');
 
 /**
  * This object should be used to evaluate natspec expression
@@ -3418,7 +3420,7 @@ var natspec = (function () {
             context[key] = obj[key];
         });
     }
-    
+
     /// generate codes, which will be evaluated
     var generateCode = function (obj) {
         return Object.keys(obj).reduce(function (acc, key) {
@@ -3440,20 +3442,20 @@ var natspec = (function () {
     /// @returns hashmap with all contract's method input variables
     var getMethodInputParams = function (method, transaction) {
         // do it with output formatter (cause we have to decode)
-        var params = abi.formatOutput(method.inputs, '0x' + transaction.params[0].data.slice(10)); 
+        var params = abi.formatOutput(method.inputs, '0x' + transaction.params[0].data.slice(10));
 
         return method.inputs.reduce(function (acc, current, index) {
             acc[current.name] = params[index];
             return acc;
         }, {});
     };
-    
+
     /// Should be called to evaluate expression
     var mapExpressionsToEvaluate = function (expression, cb) {
         var evaluatedExpression = "";
 
-        // match everything in `` quotes
-        var pattern = /\`(?:\\.|[^`\\])*\`/gim
+        // match everything in backtick
+        var pattern = /\` + "`" + `(?:\\.|[^` + "`" + `\\])*\` + "`" + `/gim
         var match;
         var lastIndex = 0;
         while ((match = pattern.exec(expression)) !== null) {
@@ -3464,9 +3466,9 @@ var natspec = (function () {
             evaluatedExpression += evaluatedPart;
             lastIndex = pattern.lastIndex;
         }
-        
+
         evaluatedExpression += expression.slice(lastIndex);
-    
+
         return evaluatedExpression;
     };
 
@@ -3478,11 +3480,11 @@ var natspec = (function () {
     var evaluateExpression = function (expression, call) {
         //var self = this;
         var context = {};
-        
+
         if (!!call) {
             try {
                 var method = getMethodWithName(call.abi, call.method);
-                var params = getMethodInputParams(method, call.transaction); 
+                var params = getMethodInputParams(method, call.transaction);
                 copyToContext(params, context);
             }
             catch (err) {
@@ -3498,7 +3500,7 @@ var natspec = (function () {
                 return fn(context).toString();
             }
             catch (err) {
-                return 'undefined'; 
+                return 'undefined';
             }
         });
 
@@ -3511,7 +3513,8 @@ var natspec = (function () {
 
 })();
 
-module.exports = natspec; 
+module.exports = natspec;
 
 
 },{"./node_modules/ethereum.js/lib/abi.js":3}]},{},[]);
+`
diff --git a/ethutil/natspec/natspec_test.go b/ethutil/natspec/natspec_test.go
index 48a9cb25c..3c70a0840 100644
--- a/ethutil/natspec/natspec_test.go
+++ b/ethutil/natspec/natspec_test.go
@@ -6,41 +6,48 @@ import (
 
 func TestNotice(t *testing.T) {
 
-	ns, err := NewNATSpec(`
+	tx := `
 	{
-            "jsonrpc": "2.0",
-            "method": "eth_call",
-            "params": [{
-                "to": "0x8521742d3f456bd237e312d6e30724960f72517a",
-                "data": "0xc6888fa1000000000000000000000000000000000000000000000000000000000000007a"
-            }],
-            "id": 6
-        }
-	`)
+    "jsonrpc": "2.0",
+    "method": "eth_call",
+    "params": [{
+        "to": "0x8521742d3f456bd237e312d6e30724960f72517a",
+        "data": "0xc6888fa1000000000000000000000000000000000000000000000000000000000000007a"
+    }],
+    "id": 6
+  }
+	`
 
+	abi := `
+	[{
+    "name": "multiply",
+    "constant": false,
+    "type": "function",
+    "inputs": [{
+      "name": "a",
+      "type": "uint256"
+    }],
+    "outputs": [{
+      "name": "d",
+      "type": "uint256"
+    }]
+  }]
+	`
+
+	desc := "Will multiply `a` by 7 and return `a * 7`."
+
+	method := "multiply"
+
+	ns, err := NewNATSpec()
 	if err != nil {
 		t.Errorf("NewNATSpec error %v", err)
 	}
 
-	ns.SetABI(`
-	[{
-            "name": "multiply",
-            "constant": false,
-            "type": "function",
-            "inputs": [{
-                "name": "a",
-                "type": "uint256"
-            }],
-            "outputs": [{
-                "name": "d",
-                "type": "uint256"
-            }]
-        }]
-	`)
-	ns.SetDescription("Will multiply `a` by 7 and return `a * 7`.")
-	ns.SetMethod("multiply")
-
-	notice := ns.Parse()
+	notice, err := ns.Notice(tx, abi, method, desc)
+
+	if err != nil {
+		t.Errorf("expected no error got %v", err)
+	}
 
 	expected := "Will multiply 122 by 7 and return 854."
 	if notice != expected {
@@ -48,4 +55,42 @@ func TestNotice(t *testing.T) {
 	} else {
 		t.Logf("returned notice \"%v\"", notice)
 	}
+
+	notice, err = ns.Notice(tx, abi, method, "Will multiply 122 by \"7\" and return 854.")
+
+	expected = "natspec.js error setting expression: (anonymous): Line 1:41 Unexpected number"
+
+	if err == nil {
+		t.Errorf("expected error, got nothing (notice: '%v')", err, notice)
+	} else {
+		if err.Error() != expected {
+			t.Errorf("expected error '%s' got '%v' (notice: '%v')", expected, err, notice)
+		}
+	}
+
+	// badDesc := "Will multiply `e` by 7 and return `a * 7`."
+	// notice, err = ns.Notice(tx, abi, method, badDesc)
+
+	// expected = "natspec.js error evaluating expression: wrong input param in expression ''"
+
+	// if err == nil {
+	// 	t.Errorf("expected error, got nothing (notice: '%v')", notice)
+	// } else {
+	// 	if err.Error() != expected {
+	// 		t.Errorf("expected error '%s' got '%v' (notice: '%v')", expected, err, notice)
+	// 	}
+	// }
+
+	notice, err = ns.Notice(tx, abi, "missing_method", desc)
+
+	expected = "natspec.js error evaluating expression: wrong input params in expression 'Will multiply `a` by 7 and return `a * 7`.'"
+
+	if err == nil {
+		t.Errorf("expected error, got nothing (notice: '%v')", notice)
+	} else {
+		if err.Error() != expected {
+			t.Errorf("expected error '%s' got '%v' (notice: '%v')", expected, err, notice)
+		}
+	}
+
 }