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state based attribute lexer
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@kbrsh
kbrsh committed Jun 10, 2019
1 parent af0a86e commit a8ff725
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Showing 4 changed files with 240 additions and 114 deletions.
175 changes: 117 additions & 58 deletions packages/moon/dist/moon.js
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Original file line number Diff line number Diff line change
Expand Up @@ -75,14 +75,6 @@
*/

var nameRE = /<([\w\d-_]+)([^>]*?)(\/?)>/g;
/**
* Capture a key, value, and expression from a list of whitespace-separated
* attributes. There cannot be a value and an expression, but both are captured
* due to the limits of regular expressions. One or both of them can be
* undefined.
*/

var attributeRE = /([\w\d-_:@]*)(?:=(?:("[^"]*"|'[^']*')|{([^=]*)}))?/g;
/**
* Capture the variables in expressions to scope them within the data
* parameter. This ignores property names and deep object accesses.
Expand Down Expand Up @@ -114,6 +106,14 @@
"\n": "\\n",
"\r": "\\r"
};
/*
* Map from attribute keys to equivalent DOM properties.
*/

var normalizeAttributeKeyMap = {
"class": "className",
"for": "htmlFor"
};
/**
* Escape text to make it usable in a JavaScript string literal.
*
Expand All @@ -138,17 +138,8 @@


function normalizeAttributeKey(key) {
switch (key) {
case "class":
return "className";

case "for":
return "htmlFor";

default:
// Other keys should ideally be camelCased.
return key;
}
var normalizedAttributeKey = normalizeAttributeKeyMap[key];
return normalizedAttributeKey === undefined ? key : normalizedAttributeKey;
}
/**
* Scope an expression to use variables within the `data` object.
Expand Down Expand Up @@ -316,41 +307,109 @@
var name = nameExec[1];
var attributesText = nameExec[2];
var closeSlash = nameExec[3];
var attributes = {};
var attributeExec = void 0; // Keep matching for new attribute key/value pairs until there are no
// more in the attribute text.

while ((attributeExec = attributeRE.exec(attributesText)) !== null) {
// Store the match and captured groups.
var attributeMatch = attributeExec[0];
var attributeKey = normalizeAttributeKey(attributeExec[1]);
var attributeValue = attributeExec[2];
var attributeExpression = attributeExec[3];

if (attributeMatch.length === 0) {
// If nothing is matched, continue searching from the next
// character. This is required because the attribute regular
// expression can have empty matches and create an infinite
// loop.
attributeRE.lastIndex += 1;
} else if (attributeKey.charCodeAt(0) === 64) {
// For events, pass the event handler and component data. Event
// handlers are assumed to be dynamic because the component data
// can change.
attributes[attributeKey] = {
value: "[" + scopeExpression(attributeExpression).value + ",data]",
isStatic: false
};
} else if (attributeExpression === undefined) {
// Set a static key-value pair. When a value isn't provided,
// the attribute is considered a Boolean value set to true.
attributes[attributeKey] = {
value: attributeValue === undefined ? "true" : attributeValue,
isStatic: true
};
} else {
// Set a potentially dynamic expression.
attributes[attributeKey] = scopeExpression(attributeExpression);
var attributes = {}; // Match attributes.

for (var j = 0; j < attributesText.length; j++) {
var charAttribute = attributesText[j];

if (!whitespaceRE.test(charAttribute)) {
var attributeKey = "";
var attributeValue = "true"; // Match an attribute key.

for (; j < attributesText.length; j++) {
charAttribute = attributesText[j];

if (whitespaceRE.test(charAttribute)) {
break;
} else if (charAttribute === "=") {
attributeValue = "";
break;
} else {
attributeKey += charAttribute;
}
} // Normalize the attribute key.


attributeKey = normalizeAttributeKey(attributeKey); // Match an attribute value if it exists.

if (attributeValue.length === 0) {
// Find a matching end quote.
var quote = attributesText[++j];

if (quote === "{") {
// For expressions, ensure that the correct closing
// delimiter is used.
quote = "}";
} else {
// For strings, add the first quote to the value.
attributeValue += quote;
} // Skip over the first quote.


j += 1; // Keep a stack of opened objects.

var opened = 0; // Iterate through the value.

for (; j < attributesText.length; j++) {
charAttribute = attributesText[j];

if (charAttribute === "{") {
// Found an open object, keep track of it.
opened += 1;
attributeValue += charAttribute;
} else if (charAttribute === quote) {
// Found a potential ending quote.
if (quote === "}") {
// If the value is an expression, ensure that all
// objects are closed.
if (opened === 0) {
if (attributeKey.charCodeAt(0) === 64) {
// For events, pass the event handler and component data. Event
// handlers are assumed to be dynamic because the component data
// can change.
attributes[attributeKey] = {
value: "[" + scopeExpression(attributeValue).value + ",data]",
isStatic: false
};
} else {
// Set a potentially dynamic expression.
attributes[attributeKey] = scopeExpression(attributeValue);
} // Exit on the quote.


break;
} else {
// If all objects aren't yet closed, mark one as closed.
attributeValue += charAttribute;
opened -= 1;
}
} else {
// If the value is a string, add the closing quote.
attributeValue += charAttribute; // Set a static key-value pair.

attributes[attributeKey] = {
value: attributeValue,
isStatic: true
}; // Exit on the quote.

break;
}
} else {
// Append characters to the value.
attributeValue += charAttribute;
}
} // Skip over the closing quote.


j += 1;
} else {
// When a value isn't provided, the attribute is considered a
// Boolean value set to true.
attributes[attributeKey] = {
value: attributeValue,
isStatic: true
};
}
}
} // Append an opening tag token with the name, attributes, and optional
// self-closing slash.
Expand All @@ -368,19 +427,19 @@
// expression token.
var expression = ""; // Keep a stack of opened objects.

var opened = 0; // Consume the input until the end of the expression.
var _opened = 0; // Consume the input until the end of the expression.

for (i += 1; i < input.length; i++) {
var _char2 = input[i];

if (_char2 === "{") {
opened += 1;
_opened += 1;
expression += _char2;
} else if (_char2 === "}") {
if (opened === 0) {
if (_opened === 0) {
break;
} else {
opened -= 1;
_opened -= 1;
expression += _char2;
}
} else {
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