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Code Issues Releases Wiki Activity

fix: linting errors (#441)

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Disable new linters which aren't compatible with this code module.

Upgrade github actions to fix caching issues.

Run go mod to bring in new styling.

Remove space on nolint declarations.

Apply all changes to whitespace as required to pass goimports linter.

Only trigger checks on pull_request which works for pulls from other
forks, where as push only works from the same repo.
This commit is contained in:
Steven Hartland
2022-10-08 00:12:19 +01:00
committed by GitHub
parent 201ab5b34f
commit 7009038f79
20 changed files with 284 additions and 265 deletions
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272
otto.go
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@@ -3,81 +3,81 @@ Package otto is a JavaScript parser and interpreter written natively in Go.
http://godoc.org/github.com/robertkrimen/otto
import (
"github.com/robertkrimen/otto"
)
import (
"github.com/robertkrimen/otto"
)
Run something in the VM
vm := otto.New()
vm.Run(`
abc = 2 + 2;
console.log("The value of abc is " + abc); // 4
`)
vm := otto.New()
vm.Run(`
abc = 2 + 2;
console.log("The value of abc is " + abc); // 4
`)
Get a value out of the VM
value, err := vm.Get("abc")
value, _ := value.ToInteger()
}
value, err := vm.Get("abc")
value, _ := value.ToInteger()
}
Set a number
vm.Set("def", 11)
vm.Run(`
console.log("The value of def is " + def);
// The value of def is 11
`)
vm.Set("def", 11)
vm.Run(`
console.log("The value of def is " + def);
// The value of def is 11
`)
Set a string
vm.Set("xyzzy", "Nothing happens.")
vm.Run(`
console.log(xyzzy.length); // 16
`)
vm.Set("xyzzy", "Nothing happens.")
vm.Run(`
console.log(xyzzy.length); // 16
`)
Get the value of an expression
value, _ = vm.Run("xyzzy.length")
{
// value is an int64 with a value of 16
value, _ := value.ToInteger()
}
value, _ = vm.Run("xyzzy.length")
{
// value is an int64 with a value of 16
value, _ := value.ToInteger()
}
An error happens
value, err = vm.Run("abcdefghijlmnopqrstuvwxyz.length")
if err != nil {
// err = ReferenceError: abcdefghijlmnopqrstuvwxyz is not defined
// If there is an error, then value.IsUndefined() is true
...
}
value, err = vm.Run("abcdefghijlmnopqrstuvwxyz.length")
if err != nil {
// err = ReferenceError: abcdefghijlmnopqrstuvwxyz is not defined
// If there is an error, then value.IsUndefined() is true
...
}
Set a Go function
vm.Set("sayHello", func(call otto.FunctionCall) otto.Value {
fmt.Printf("Hello, %s.\n", call.Argument(0).String())
return otto.Value{}
})
vm.Set("sayHello", func(call otto.FunctionCall) otto.Value {
fmt.Printf("Hello, %s.\n", call.Argument(0).String())
return otto.Value{}
})
Set a Go function that returns something useful
vm.Set("twoPlus", func(call otto.FunctionCall) otto.Value {
right, _ := call.Argument(0).ToInteger()
result, _ := vm.ToValue(2 + right)
return result
})
vm.Set("twoPlus", func(call otto.FunctionCall) otto.Value {
right, _ := call.Argument(0).ToInteger()
result, _ := vm.ToValue(2 + right)
return result
})
Use the functions in JavaScript
result, _ = vm.Run(`
sayHello("Xyzzy"); // Hello, Xyzzy.
sayHello(); // Hello, undefined
result, _ = vm.Run(`
sayHello("Xyzzy"); // Hello, Xyzzy.
sayHello(); // Hello, undefined
result = twoPlus(2.0); // 4
`)
result = twoPlus(2.0); // 4
`)
Parser
# Parser
A separate parser is available in the parser package if you're just interested in building an AST.
@@ -85,23 +85,23 @@ http://godoc.org/github.com/robertkrimen/otto/parser
Parse and return an AST
filename := "" // A filename is optional
src := `
// Sample xyzzy example
(function(){
if (3.14159 > 0) {
console.log("Hello, World.");
return;
}
filename := "" // A filename is optional
src := `
// Sample xyzzy example
(function(){
if (3.14159 > 0) {
console.log("Hello, World.");
return;
}
var xyzzy = NaN;
console.log("Nothing happens.");
return xyzzy;
})();
`
var xyzzy = NaN;
console.log("Nothing happens.");
return xyzzy;
})();
`
// Parse some JavaScript, yielding a *ast.Program and/or an ErrorList
program, err := parser.ParseFile(nil, filename, src, 0)
// Parse some JavaScript, yielding a *ast.Program and/or an ErrorList
program, err := parser.ParseFile(nil, filename, src, 0)
otto
@@ -126,24 +126,24 @@ Optionally include the JavaScript utility-belt library, underscore, with this im
For more information: http://github.com/robertkrimen/otto/tree/master/underscore
Caveat Emptor
# Caveat Emptor
The following are some limitations with otto:
* "use strict" will parse, but does nothing.
* The regular expression engine (re2/regexp) is not fully compatible with the ECMA5 specification.
* Otto targets ES5. ES6 features (eg: Typed Arrays) are not supported.
- "use strict" will parse, but does nothing.
- The regular expression engine (re2/regexp) is not fully compatible with the ECMA5 specification.
- Otto targets ES5. ES6 features (eg: Typed Arrays) are not supported.
Regular Expression Incompatibility
# Regular Expression Incompatibility
Go translates JavaScript-style regular expressions into something that is "regexp" compatible via `parser.TransformRegExp`.
Unfortunately, RegExp requires backtracking for some patterns, and backtracking is not supported by the standard Go engine: https://code.google.com/p/re2/wiki/Syntax
Therefore, the following syntax is incompatible:
(?=) // Lookahead (positive), currently a parsing error
(?!) // Lookahead (backhead), currently a parsing error
\1 // Backreference (\1, \2, \3, ...), currently a parsing error
(?=) // Lookahead (positive), currently a parsing error
(?!) // Lookahead (backhead), currently a parsing error
\1 // Backreference (\1, \2, \3, ...), currently a parsing error
A brief discussion of these limitations: "Regexp (?!re)" https://groups.google.com/forum/?fromgroups=#%21topic/golang-nuts/7qgSDWPIh_E
@@ -152,57 +152,57 @@ More information about re2: https://code.google.com/p/re2/
In addition to the above, re2 (Go) has a different definition for \s: [\t\n\f\r ].
The JavaScript definition, on the other hand, also includes \v, Unicode "Separator, Space", etc.
Halting Problem
# Halting Problem
If you want to stop long running executions (like third-party code), you can use the interrupt channel to do this:
package main
package main
import (
"errors"
"fmt"
"os"
"time"
import (
"errors"
"fmt"
"os"
"time"
"github.com/robertkrimen/otto"
)
"github.com/robertkrimen/otto"
)
var halt = errors.New("Stahp")
var halt = errors.New("Stahp")
func main() {
runUnsafe(`var abc = [];`)
runUnsafe(`
while (true) {
// Loop forever
}`)
}
func main() {
runUnsafe(`var abc = [];`)
runUnsafe(`
while (true) {
// Loop forever
}`)
}
func runUnsafe(unsafe string) {
start := time.Now()
defer func() {
duration := time.Since(start)
if caught := recover(); caught != nil {
if caught == halt {
fmt.Fprintf(os.Stderr, "Some code took to long! Stopping after: %v\n", duration)
return
}
panic(caught) // Something else happened, repanic!
}
fmt.Fprintf(os.Stderr, "Ran code successfully: %v\n", duration)
}()
func runUnsafe(unsafe string) {
start := time.Now()
defer func() {
duration := time.Since(start)
if caught := recover(); caught != nil {
if caught == halt {
fmt.Fprintf(os.Stderr, "Some code took to long! Stopping after: %v\n", duration)
return
}
panic(caught) // Something else happened, repanic!
}
fmt.Fprintf(os.Stderr, "Ran code successfully: %v\n", duration)
}()
vm := otto.New()
vm.Interrupt = make(chan func(), 1) // The buffer prevents blocking
vm := otto.New()
vm.Interrupt = make(chan func(), 1) // The buffer prevents blocking
go func() {
time.Sleep(2 * time.Second) // Stop after two seconds
vm.Interrupt <- func() {
panic(halt)
}
}()
go func() {
time.Sleep(2 * time.Second) // Stop after two seconds
vm.Interrupt <- func() {
panic(halt)
}
}()
vm.Run(unsafe) // Here be dragons (risky code)
}
vm.Run(unsafe) // Here be dragons (risky code)
}
Where is setTimeout/setInterval?
@@ -220,7 +220,6 @@ Here is some more discussion of the issue:
* http://en.wikipedia.org/wiki/Reentrancy_%28computing%29
* http://aaroncrane.co.uk/2009/02/perl_safe_signals/
*/
package otto
@@ -273,7 +272,6 @@ func (otto *Otto) clone() *Otto {
// src may also be a Script.
//
// src may also be a Program, but if the AST has been modified, then runtime behavior is undefined.
//
func Run(src interface{}) (*Otto, Value, error) {
otto := New()
value, err := otto.Run(src) // This already does safety checking
@@ -290,7 +288,6 @@ func Run(src interface{}) (*Otto, Value, error) {
// src may also be a Script.
//
// src may also be a Program, but if the AST has been modified, then runtime behavior is undefined.
//
func (self Otto) Run(src interface{}) (Value, error) {
value, err := self.runtime.cmpl_run(src, nil)
if !value.safe() {
@@ -524,16 +521,15 @@ func (self Otto) ContextSkip(limit int, skipNative bool) (ctx Context) {
// Call will invoke the function constructor rather than performing a function call.
// In this case, the this argument has no effect.
//
// // value is a String object
// value, _ := vm.Call("Object", nil, "Hello, World.")
// // value is a String object
// value, _ := vm.Call("Object", nil, "Hello, World.")
//
// // Likewise...
// value, _ := vm.Call("new Object", nil, "Hello, World.")
//
// // This will perform a concat on the given array and return the result
// // value is [ 1, 2, 3, undefined, 4, 5, 6, 7, "abc" ]
// value, _ := vm.Call(`[ 1, 2, 3, undefined, 4 ].concat`, nil, 5, 6, 7, "abc")
// // Likewise...
// value, _ := vm.Call("new Object", nil, "Hello, World.")
//
// // This will perform a concat on the given array and return the result
// // value is [ 1, 2, 3, undefined, 4, 5, 6, 7, "abc" ]
// value, _ := vm.Call(`[ 1, 2, 3, undefined, 4 ].concat`, nil, 5, 6, 7, "abc")
func (self Otto) Call(source string, this interface{}, argumentList ...interface{}) (Value, error) {
thisValue := Value{}
@@ -602,16 +598,16 @@ func (self Otto) Call(source string, this interface{}, argumentList ...interface
//
// For example, accessing an existing object:
//
// object, _ := vm.Object(`Number`)
// object, _ := vm.Object(`Number`)
//
// Or, creating a new object:
//
// object, _ := vm.Object(`({ xyzzy: "Nothing happens." })`)
// object, _ := vm.Object(`({ xyzzy: "Nothing happens." })`)
//
// Or, creating and assigning an object:
//
// object, _ := vm.Object(`xyzzy = {}`)
// object.Set("volume", 11)
// object, _ := vm.Object(`xyzzy = {}`)
// object.Set("volume", 11)
//
// If there is an error (like the source does not result in an object), then
// nil and an error is returned.
@@ -667,15 +663,14 @@ func _newObject(object *_object, value Value) *Object {
//
// It is essentially equivalent to:
//
// var method, _ := object.Get(name)
// method.Call(object, argumentList...)
// var method, _ := object.Get(name)
// method.Call(object, argumentList...)
//
// An undefined value and an error will result if:
//
// 1. There is an error during conversion of the argument list
// 2. The property is not actually a function
// 3. An (uncaught) exception is thrown
//
// 1. There is an error during conversion of the argument list
// 2. The property is not actually a function
// 3. An (uncaught) exception is thrown
func (self Object) Call(name string, argumentList ...interface{}) (Value, error) {
// TODO: Insert an example using JavaScript below...
// e.g., Object("JSON").Call("stringify", ...)
@@ -756,15 +751,14 @@ func (self Object) KeysByParent() [][]string {
//
// The return value will (generally) be one of:
//
// Object
// Function
// Array
// String
// Number
// Boolean
// Date
// RegExp
//
// Object
// Function
// Array
// String
// Number
// Boolean
// Date
// RegExp
func (self Object) Class() string {
return self.object.class
}