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

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) {
+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 expression = \"" + desc + "\";")
+	if _, err = self.jsvm.Run("var abi = " + abi + ";"); err != nil {
-	return
+		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) SetABI(abi string) (err error) {
+	if _, err = self.jsvm.Run("var expression = \"" + expression + "\";"); err != nil {
-
+		return "", fmt.Errorf("natspec.js error setting expression: %v", err)
-	_, err = self.jsvm.Run("var abi = " + abi + ";")
+	}
-	return
-
-}
-
-func (self *NatSpec) SetMethod(method string) (err error) {
-
-	_, err = self.jsvm.Run("var method = '" + method + "';")
-	return
-
-}
-
-func (self *NatSpec) Parse() string {
 
 	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)
 	}
-	return value.String()
+	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)
+	}
+	if len(value.String()) == 0 {
+		return "", fmt.Errorf("natspec.js error evaluating expression")
+	}
+
+	return value.String(), nil
 
 }

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
@@ -3452,8 +3454,8 @@ var natspec = (function () {
     var mapExpressionsToEvaluate = function (expression, cb) {
         var evaluatedExpression = "";
 
-        // match everything in `` quotes
+        // match everything in backtick
-        var pattern = /\`(?:\\.|[^`\\])*\`/gim
+        var pattern = /\` + "`" + `(?:\\.|[^` + "`" + `\\])*\` + "`" + `/gim
         var match;
         var lastIndex = 0;
         while ((match = pattern.exec(expression)) !== null) {
@@ -3515,3 +3517,4 @@ module.exports = natspec;
 
 
 },{"./node_modules/ethereum.js/lib/abi.js":3}]},{},[]);
+`

ethutil/natspec/natspec_test.go

@@ -6,41 +6,48 @@ import (
 
 func TestNotice(t *testing.T) {
 
-	ns, err := NewNATSpec(`
+	tx := `
 	{
-            "jsonrpc": "2.0",
+    "jsonrpc": "2.0",
-            "method": "eth_call",
+    "method": "eth_call",
-            "params": [{
+    "params": [{
-                "to": "0x8521742d3f456bd237e312d6e30724960f72517a",
+        "to": "0x8521742d3f456bd237e312d6e30724960f72517a",
-                "data": "0xc6888fa1000000000000000000000000000000000000000000000000000000000000007a"
+        "data": "0xc6888fa1000000000000000000000000000000000000000000000000000000000000007a"
-            }],
+    }],
-            "id": 6
+    "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(`
+	notice, err := ns.Notice(tx, abi, method, desc)
-	[{
-            "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()
+	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)
+		}
+	}
+
 }