Skip to content
This repository was archived by the owner on Apr 12, 2024. It is now read-only.

feat($parse): add support for ternary operators to parser #2482

Closed
wants to merge 2 commits into from
Closed

feat($parse): add support for ternary operators to parser #2482

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
16af3b8
feat($parse): add support for ternary operators to parser
zachsnow Apr 23, 2013
f7da538
Clarify parsing of ternaries using more descriptive variable names; i…
zachsnow May 12, 2013
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
35 changes: 32 additions & 3 deletions src/ng/parse.js
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -58,7 +58,7 @@ function lex(text, csp){
(token=tokens[tokens.length-1])) {
token.json = token.text.indexOf('.') == -1;
}
} else if (is('(){}[].,;:')) {
} else if (is('(){}[].,;:?')) {
tokens.push({
index:index,
text:ch,
Expand Down Expand Up @@ -359,6 +359,14 @@ function parser(text, json, $filter, csp){
});
}

function ternaryFn(left, middle, right){
return extend(function(self, locals){
return left(self, locals) ? middle(self, locals) : right(self, locals);
}, {
constant: left.constant && middle.constant && right.constant
});
}

function binaryFn(left, fn, right) {
return extend(function(self, locals) {
return fn(self, locals, left, right);
Expand Down Expand Up @@ -427,17 +435,18 @@ function parser(text, json, $filter, csp){
function expression() {
return assignment();
}


function _assignment() {
var left = logicalOR();
var left = ternary();
var right;
var token;
if ((token = expect('='))) {
if (!left.assign) {
throwError("implies assignment but [" +
text.substring(0, token.index) + "] can not be assigned to", token);
}
right = logicalOR();
right = ternary();
return function(self, locals){
return left.assign(self, right(self, locals), locals);
};
Expand All @@ -446,6 +455,26 @@ function parser(text, json, $filter, csp){
}
}

function ternary() {
var left = logicalOR();
var middle;
var right;
Copy link
Contributor

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

right is never used

var token;
if((token = expect('?'))){
middle = ternary();
if((token = expect(':'))){
right = ternary();
return ternaryFn(left, middle, right);
}
else {
throwError('expected :', token);
}
}
else {
return left;
}
}

function logicalOR() {
var left = logicalAND();
var token;
Expand Down
72 changes: 72 additions & 0 deletions test/ng/parseSpec.js
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -103,6 +103,14 @@ describe('parser', function() {
expect(tokens[7].text).toEqual('===');
expect(tokens[8].text).toEqual('!==');
});

it('should tokenize logical and ternary', function() {
var tokens = lex("&& || ? :");
expect(tokens[0].text).toEqual('&&');
expect(tokens[1].text).toEqual('||');
expect(tokens[2].text).toEqual('?');
expect(tokens[3].text).toEqual(':');
});

it('should tokenize statements', function() {
var tokens = lex("a;b;");
Expand Down Expand Up @@ -220,6 +228,70 @@ describe('parser', function() {
expect(scope.$eval("0||2")).toEqual(0||2);
expect(scope.$eval("0||1&&2")).toEqual(0||1&&2);
});

it('should parse ternary', function(){
var returnTrue = scope.returnTrue = function(){ return true; };
var returnFalse = scope.returnFalse = function(){ return false; };
var returnString = scope.returnString = function(){ return 'asd'; };
var returnInt = scope.returnInt = function(){ return 123; };
var identity = scope.identity = function(x){ return x; };

// Simple.
expect(scope.$eval('0?0:2')).toEqual(0?0:2);
expect(scope.$eval('1?0:2')).toEqual(1?0:2);

// Nested on the left.
expect(scope.$eval('0?0?0:0:2')).toEqual(0?0?0:0:2);
expect(scope.$eval('1?0?0:0:2')).toEqual(1?0?0:0:2);
expect(scope.$eval('0?1?0:0:2')).toEqual(0?1?0:0:2);
expect(scope.$eval('0?0?1:0:2')).toEqual(0?0?1:0:2);
expect(scope.$eval('0?0?0:2:3')).toEqual(0?0?0:2:3);
expect(scope.$eval('1?1?0:0:2')).toEqual(1?1?0:0:2);
expect(scope.$eval('1?1?1:0:2')).toEqual(1?1?1:0:2);
expect(scope.$eval('1?1?1:2:3')).toEqual(1?1?1:2:3);
expect(scope.$eval('1?1?1:2:3')).toEqual(1?1?1:2:3);

// Nested on the right.
expect(scope.$eval('0?0:0?0:2')).toEqual(0?0:0?0:2);
expect(scope.$eval('1?0:0?0:2')).toEqual(1?0:0?0:2);
expect(scope.$eval('0?1:0?0:2')).toEqual(0?1:0?0:2);
expect(scope.$eval('0?0:1?0:2')).toEqual(0?0:1?0:2);
expect(scope.$eval('0?0:0?2:3')).toEqual(0?0:0?2:3);
expect(scope.$eval('1?1:0?0:2')).toEqual(1?1:0?0:2);
expect(scope.$eval('1?1:1?0:2')).toEqual(1?1:1?0:2);
expect(scope.$eval('1?1:1?2:3')).toEqual(1?1:1?2:3);
expect(scope.$eval('1?1:1?2:3')).toEqual(1?1:1?2:3);

// Precedence with respect to logical operators.
expect(scope.$eval('0&&1?0:1')).toEqual(0&&1?0:1);
expect(scope.$eval('1||0?0:0')).toEqual(1||0?0:0);

expect(scope.$eval('0?0&&1:2')).toEqual(0?0&&1:2);
expect(scope.$eval('0?1&&1:2')).toEqual(0?1&&1:2);
expect(scope.$eval('0?0||0:1')).toEqual(0?0||0:1);
expect(scope.$eval('0?0||1:2')).toEqual(0?0||1:2);

expect(scope.$eval('1?0&&1:2')).toEqual(1?0&&1:2);
expect(scope.$eval('1?1&&1:2')).toEqual(1?1&&1:2);
expect(scope.$eval('1?0||0:1')).toEqual(1?0||0:1);
expect(scope.$eval('1?0||1:2')).toEqual(1?0||1:2);

expect(scope.$eval('0?1:0&&1')).toEqual(0?1:0&&1);
expect(scope.$eval('0?2:1&&1')).toEqual(0?2:1&&1);
expect(scope.$eval('0?1:0||0')).toEqual(0?1:0||0);
expect(scope.$eval('0?2:0||1')).toEqual(0?2:0||1);

expect(scope.$eval('1?1:0&&1')).toEqual(1?1:0&&1);
expect(scope.$eval('1?2:1&&1')).toEqual(1?2:1&&1);
expect(scope.$eval('1?1:0||0')).toEqual(1?1:0||0);
expect(scope.$eval('1?2:0||1')).toEqual(1?2:0||1);

// Function calls.
expect(scope.$eval('returnTrue() ? returnString() : returnInt()')).toEqual(returnTrue() ? returnString() : returnInt());
expect(scope.$eval('returnFalse() ? returnString() : returnInt()')).toEqual(returnFalse() ? returnString() : returnInt());
expect(scope.$eval('returnTrue() ? returnString() : returnInt()')).toEqual(returnTrue() ? returnString() : returnInt());
expect(scope.$eval('identity(returnFalse() ? returnString() : returnInt())')).toEqual(identity(returnFalse() ? returnString() : returnInt()));
});

it('should parse string', function() {
expect(scope.$eval("'a' + 'b c'")).toEqual("ab c");
Expand Down