Website Structure

Frontend-Learner/node_modules/@vercel/nft/out/utils/static-eval.js

@@ -0,0 +1,579 @@
+"use strict";
+Object.defineProperty(exports, "__esModule", { value: true });
+exports.wildcardRegEx = exports.WILDCARD = exports.FUNCTION = exports.UNKNOWN = void 0;
+exports.evaluate = evaluate;
+async function evaluate(ast, vars = {}, computeBranches = true) {
+    const state = {
+        computeBranches,
+        vars,
+    };
+    return walk(ast);
+    // walk returns:
+    // 1. Single known value: { value: value }
+    // 2. Conditional value: { test, ifTrue, else }
+    // 3. Unknown value: undefined
+    function walk(node) {
+        const visitor = visitors[node.type];
+        if (visitor) {
+            return visitor.call(state, node, walk);
+        }
+        return undefined;
+    }
+}
+exports.UNKNOWN = Symbol();
+exports.FUNCTION = Symbol();
+exports.WILDCARD = '\x1a';
+exports.wildcardRegEx = /\x1a/g;
+function countWildcards(str) {
+    exports.wildcardRegEx.lastIndex = 0;
+    let cnt = 0;
+    while (exports.wildcardRegEx.exec(str))
+        cnt++;
+    return cnt;
+}
+const visitors = {
+    ArrayExpression: async function ArrayExpression(node, walk) {
+        const arr = [];
+        for (let i = 0, l = node.elements.length; i < l; i++) {
+            if (node.elements[i] === null) {
+                arr.push(null);
+                continue;
+            }
+            const x = await walk(node.elements[i]);
+            if (!x)
+                return;
+            if ('value' in x === false)
+                return;
+            arr.push(x.value);
+        }
+        return { value: arr };
+    },
+    ArrowFunctionExpression: async function (node, walk) {
+        // () => val support only
+        if (node.params.length === 0 &&
+            !node.generator &&
+            !node.async &&
+            node.expression) {
+            const innerValue = await walk(node.body);
+            if (!innerValue || !('value' in innerValue))
+                return;
+            return {
+                value: {
+                    [exports.FUNCTION]: () => innerValue.value,
+                },
+            };
+        }
+        return undefined;
+    },
+    BinaryExpression: async function BinaryExpression(node, walk) {
+        const op = node.operator;
+        let l = await walk(node.left);
+        if (!l && op !== '+')
+            return;
+        let r = await walk(node.right);
+        if (!l && !r)
+            return;
+        if (!l) {
+            // UNKNOWN + 'str' -> wildcard string value
+            if (this.computeBranches &&
+                r &&
+                'value' in r &&
+                typeof r.value === 'string')
+                return {
+                    value: exports.WILDCARD + r.value,
+                    wildcards: [node.left, ...(r.wildcards || [])],
+                };
+            return;
+        }
+        if (!r) {
+            // 'str' + UKNOWN -> wildcard string value
+            if (this.computeBranches && op === '+') {
+                if (l && 'value' in l && typeof l.value === 'string')
+                    return {
+                        value: l.value + exports.WILDCARD,
+                        wildcards: [...(l.wildcards || []), node.right],
+                    };
+            }
+            // A || UNKNOWN -> A if A is truthy
+            if (!('test' in l) && op === '||' && l.value)
+                return l;
+            return;
+        }
+        if ('test' in l && 'value' in r) {
+            const v = r.value;
+            if (op === '==')
+                return { test: l.test, ifTrue: l.ifTrue == v, else: l.else == v };
+            if (op === '===')
+                return { test: l.test, ifTrue: l.ifTrue === v, else: l.else === v };
+            if (op === '!=')
+                return { test: l.test, ifTrue: l.ifTrue != v, else: l.else != v };
+            if (op === '!==')
+                return { test: l.test, ifTrue: l.ifTrue !== v, else: l.else !== v };
+            if (op === '+')
+                return { test: l.test, ifTrue: l.ifTrue + v, else: l.else + v };
+            if (op === '-')
+                return { test: l.test, ifTrue: l.ifTrue - v, else: l.else - v };
+            if (op === '*')
+                return { test: l.test, ifTrue: l.ifTrue * v, else: l.else * v };
+            if (op === '/')
+                return { test: l.test, ifTrue: l.ifTrue / v, else: l.else / v };
+            if (op === '%')
+                return { test: l.test, ifTrue: l.ifTrue % v, else: l.else % v };
+            if (op === '<')
+                return { test: l.test, ifTrue: l.ifTrue < v, else: l.else < v };
+            if (op === '<=')
+                return { test: l.test, ifTrue: l.ifTrue <= v, else: l.else <= v };
+            if (op === '>')
+                return { test: l.test, ifTrue: l.ifTrue > v, else: l.else > v };
+            if (op === '>=')
+                return { test: l.test, ifTrue: l.ifTrue >= v, else: l.else >= v };
+            if (op === '|')
+                return { test: l.test, ifTrue: l.ifTrue | v, else: l.else | v };
+            if (op === '&')
+                return { test: l.test, ifTrue: l.ifTrue & v, else: l.else & v };
+            if (op === '^')
+                return { test: l.test, ifTrue: l.ifTrue ^ v, else: l.else ^ v };
+            if (op === '&&')
+                return { test: l.test, ifTrue: l.ifTrue && v, else: l.else && v };
+            if (op === '||')
+                return { test: l.test, ifTrue: l.ifTrue || v, else: l.else || v };
+        }
+        else if ('test' in r && 'value' in l) {
+            const v = l.value;
+            if (op === '==')
+                return { test: r.test, ifTrue: v == r.ifTrue, else: v == r.else };
+            if (op === '===')
+                return { test: r.test, ifTrue: v === r.ifTrue, else: v === r.else };
+            if (op === '!=')
+                return { test: r.test, ifTrue: v != r.ifTrue, else: v != r.else };
+            if (op === '!==')
+                return { test: r.test, ifTrue: v !== r.ifTrue, else: v !== r.else };
+            if (op === '+')
+                return { test: r.test, ifTrue: v + r.ifTrue, else: v + r.else };
+            if (op === '-')
+                return { test: r.test, ifTrue: v - r.ifTrue, else: v - r.else };
+            if (op === '*')
+                return { test: r.test, ifTrue: v * r.ifTrue, else: v * r.else };
+            if (op === '/')
+                return { test: r.test, ifTrue: v / r.ifTrue, else: v / r.else };
+            if (op === '%')
+                return { test: r.test, ifTrue: v % r.ifTrue, else: v % r.else };
+            if (op === '<')
+                return { test: r.test, ifTrue: v < r.ifTrue, else: v < r.else };
+            if (op === '<=')
+                return { test: r.test, ifTrue: v <= r.ifTrue, else: v <= r.else };
+            if (op === '>')
+                return { test: r.test, ifTrue: v > r.ifTrue, else: v > r.else };
+            if (op === '>=')
+                return { test: r.test, ifTrue: v >= r.ifTrue, else: v >= r.else };
+            if (op === '|')
+                return { test: r.test, ifTrue: v | r.ifTrue, else: v | r.else };
+            if (op === '&')
+                return { test: r.test, ifTrue: v & r.ifTrue, else: v & r.else };
+            if (op === '^')
+                return { test: r.test, ifTrue: v ^ r.ifTrue, else: v ^ r.else };
+            if (op === '&&')
+                return { test: r.test, ifTrue: v && r.ifTrue, else: l && r.else };
+            if (op === '||')
+                return { test: r.test, ifTrue: v || r.ifTrue, else: l || r.else };
+        }
+        else if ('value' in l && 'value' in r) {
+            if (op === '==')
+                return { value: l.value == r.value };
+            if (op === '===')
+                return { value: l.value === r.value };
+            if (op === '!=')
+                return { value: l.value != r.value };
+            if (op === '!==')
+                return { value: l.value !== r.value };
+            if (op === '+') {
+                const val = { value: l.value + r.value };
+                let wildcards = [];
+                if ('wildcards' in l && l.wildcards) {
+                    wildcards = wildcards.concat(l.wildcards);
+                }
+                if ('wildcards' in r && r.wildcards) {
+                    wildcards = wildcards.concat(r.wildcards);
+                }
+                if (wildcards.length > 0) {
+                    val.wildcards = wildcards;
+                }
+                return val;
+            }
+            if (op === '-')
+                return { value: l.value - r.value };
+            if (op === '*')
+                return { value: l.value * r.value };
+            if (op === '/')
+                return { value: l.value / r.value };
+            if (op === '%')
+                return { value: l.value % r.value };
+            if (op === '<')
+                return { value: l.value < r.value };
+            if (op === '<=')
+                return { value: l.value <= r.value };
+            if (op === '>')
+                return { value: l.value > r.value };
+            if (op === '>=')
+                return { value: l.value >= r.value };
+            if (op === '|')
+                return { value: l.value | r.value };
+            if (op === '&')
+                return { value: l.value & r.value };
+            if (op === '^')
+                return { value: l.value ^ r.value };
+            if (op === '&&')
+                return { value: l.value && r.value };
+            if (op === '||')
+                return { value: l.value || r.value };
+        }
+        return;
+    },
+    CallExpression: async function CallExpression(node, walk) {
+        const callee = await walk(node.callee);
+        if (!callee || 'test' in callee)
+            return;
+        let fn = callee.value;
+        if (typeof fn === 'object' && fn !== null)
+            fn = fn[exports.FUNCTION];
+        if (typeof fn !== 'function')
+            return;
+        let ctx = null;
+        if (node.callee.object) {
+            ctx = await walk(node.callee.object);
+            ctx = ctx && 'value' in ctx && ctx.value ? ctx.value : null;
+        }
+        // we allow one conditional argument to create a conditional expression
+        let predicate;
+        let args = [];
+        let argsElse;
+        let allWildcards = node.arguments.length > 0 && node.callee.property?.name !== 'concat';
+        const wildcards = [];
+        for (let i = 0, l = node.arguments.length; i < l; i++) {
+            let x = await walk(node.arguments[i]);
+            if (x) {
+                allWildcards = false;
+                if ('value' in x && typeof x.value === 'string' && x.wildcards)
+                    x.wildcards.forEach((w) => wildcards.push(w));
+            }
+            else {
+                if (!this.computeBranches)
+                    return;
+                // this works because provided static functions
+                // operate on known string inputs
+                x = { value: exports.WILDCARD };
+                wildcards.push(node.arguments[i]);
+            }
+            if ('test' in x) {
+                if (wildcards.length)
+                    return;
+                if (predicate)
+                    return;
+                predicate = x.test;
+                argsElse = args.concat([]);
+                args.push(x.ifTrue);
+                argsElse.push(x.else);
+            }
+            else {
+                args.push(x.value);
+                if (argsElse)
+                    argsElse.push(x.value);
+            }
+        }
+        if (allWildcards)
+            return;
+        try {
+            const result = await fn.apply(ctx, args);
+            if (result === exports.UNKNOWN)
+                return;
+            if (!predicate) {
+                if (wildcards.length) {
+                    if (typeof result !== 'string' ||
+                        countWildcards(result) !== wildcards.length)
+                        return;
+                    return { value: result, wildcards };
+                }
+                return { value: result };
+            }
+            const resultElse = await fn.apply(ctx, argsElse);
+            if (result === exports.UNKNOWN)
+                return;
+            return { test: predicate, ifTrue: result, else: resultElse };
+        }
+        catch (e) {
+            return;
+        }
+    },
+    ConditionalExpression: async function ConditionalExpression(node, walk) {
+        const val = await walk(node.test);
+        if (val && 'value' in val)
+            return val.value ? walk(node.consequent) : walk(node.alternate);
+        if (!this.computeBranches)
+            return;
+        const thenValue = await walk(node.consequent);
+        if (!thenValue || 'wildcards' in thenValue || 'test' in thenValue)
+            return;
+        const elseValue = await walk(node.alternate);
+        if (!elseValue || 'wildcards' in elseValue || 'test' in elseValue)
+            return;
+        return {
+            test: node.test,
+            ifTrue: thenValue.value,
+            else: elseValue.value,
+        };
+    },
+    ExpressionStatement: async function ExpressionStatement(node, walk) {
+        return walk(node.expression);
+    },
+    Identifier: async function Identifier(node, _walk) {
+        if (Object.hasOwnProperty.call(this.vars, node.name))
+            return this.vars[node.name];
+        return undefined;
+    },
+    Literal: async function Literal(node, _walk) {
+        return { value: node.value };
+    },
+    MemberExpression: async function MemberExpression(node, walk) {
+        const obj = await walk(node.object);
+        if (!obj || 'test' in obj || typeof obj.value === 'function') {
+            return undefined;
+        }
+        if (node.property.type === 'Identifier') {
+            if (typeof obj.value === 'string' && node.property.name === 'concat') {
+                return {
+                    value: {
+                        [exports.FUNCTION]: (...args) => obj.value.concat(args),
+                    },
+                };
+            }
+            if (typeof obj.value === 'object' && obj.value !== null) {
+                const objValue = obj.value;
+                if (node.computed) {
+                    // See if we can compute the computed property
+                    const computedProp = await walk(node.property);
+                    if (computedProp && 'value' in computedProp && computedProp.value) {
+                        const val = objValue[computedProp.value];
+                        if (val === exports.UNKNOWN)
+                            return undefined;
+                        return { value: val };
+                    }
+                    // Special case for empty object
+                    if (!objValue[exports.UNKNOWN] && Object.keys(obj).length === 0) {
+                        return { value: undefined };
+                    }
+                }
+                else if (node.property.name in objValue) {
+                    const val = objValue[node.property.name];
+                    if (val === exports.UNKNOWN)
+                        return undefined;
+                    return { value: val };
+                }
+                else if (objValue[exports.UNKNOWN])
+                    return undefined;
+            }
+            else {
+                return { value: undefined };
+            }
+        }
+        const prop = await walk(node.property);
+        if (!prop || 'test' in prop)
+            return undefined;
+        if (typeof obj.value === 'object' && obj.value !== null) {
+            //@ts-ignore
+            if (prop.value in obj.value) {
+                //@ts-ignore
+                const val = obj.value[prop.value];
+                if (val === exports.UNKNOWN)
+                    return undefined;
+                return { value: val };
+            }
+            //@ts-ignore
+            else if (obj.value[exports.UNKNOWN]) {
+                return undefined;
+            }
+        }
+        else {
+            return { value: undefined };
+        }
+        return undefined;
+    },
+    MetaProperty: async function MetaProperty(node) {
+        if (node.meta.name === 'import' && node.property.name === 'meta')
+            return { value: this.vars['import.meta'] };
+        return undefined;
+    },
+    NewExpression: async function NewExpression(node, walk) {
+        // new URL('./local', parent)
+        const cls = await walk(node.callee);
+        if (cls && 'value' in cls && cls.value === URL && node.arguments.length) {
+            const arg = await walk(node.arguments[0]);
+            if (!arg)
+                return undefined;
+            let parent = null;
+            if (node.arguments[1]) {
+                parent = await walk(node.arguments[1]);
+                if (!parent || !('value' in parent))
+                    return undefined;
+            }
+            if ('value' in arg) {
+                if (parent) {
+                    try {
+                        return { value: new URL(arg.value, parent.value) };
+                    }
+                    catch {
+                        return undefined;
+                    }
+                }
+                try {
+                    return { value: new URL(arg.value) };
+                }
+                catch {
+                    return undefined;
+                }
+            }
+            else {
+                const test = arg.test;
+                if (parent) {
+                    try {
+                        return {
+                            test,
+                            ifTrue: new URL(arg.ifTrue, parent.value),
+                            else: new URL(arg.else, parent.value),
+                        };
+                    }
+                    catch {
+                        return undefined;
+                    }
+                }
+                try {
+                    return {
+                        test,
+                        ifTrue: new URL(arg.ifTrue),
+                        else: new URL(arg.else),
+                    };
+                }
+                catch {
+                    return undefined;
+                }
+            }
+        }
+        return undefined;
+    },
+    ObjectExpression: async function ObjectExpression(node, walk) {
+        const obj = {};
+        for (let i = 0; i < node.properties.length; i++) {
+            const prop = node.properties[i];
+            const keyValue = prop.computed
+                ? walk(prop.key)
+                : prop.key && { value: prop.key.name || prop.key.value };
+            if (!keyValue || 'test' in keyValue)
+                return;
+            const value = await walk(prop.value);
+            if (!value || 'test' in value)
+                return;
+            //@ts-ignore
+            if (value.value === exports.UNKNOWN)
+                return;
+            //@ts-ignore
+            obj[keyValue.value] = value.value;
+        }
+        return { value: obj };
+    },
+    SequenceExpression: async function SequenceExpression(node, walk) {
+        if ('expressions' in node &&
+            node.expressions.length === 2 &&
+            node.expressions[0].type === 'Literal' &&
+            node.expressions[0].value === 0 &&
+            node.expressions[1].type === 'MemberExpression') {
+            const arg = await walk(node.expressions[1]);
+            return arg;
+        }
+        return undefined;
+    },
+    TemplateLiteral: async function TemplateLiteral(node, walk) {
+        let val = { value: '' };
+        for (var i = 0; i < node.expressions.length; i++) {
+            if ('value' in val) {
+                val.value += node.quasis[i].value.cooked;
+            }
+            else {
+                val.ifTrue += node.quasis[i].value.cooked;
+                val.else += node.quasis[i].value.cooked;
+            }
+            let exprValue = await walk(node.expressions[i]);
+            if (!exprValue) {
+                if (!this.computeBranches)
+                    return undefined;
+                exprValue = { value: exports.WILDCARD, wildcards: [node.expressions[i]] };
+            }
+            if ('value' in exprValue) {
+                if ('value' in val) {
+                    val.value += exprValue.value;
+                    if (exprValue.wildcards)
+                        val.wildcards = [...(val.wildcards || []), ...exprValue.wildcards];
+                }
+                else {
+                    if (exprValue.wildcards)
+                        return;
+                    val.ifTrue += exprValue.value;
+                    val.else += exprValue.value;
+                }
+            }
+            else if ('value' in val) {
+                if ('wildcards' in val) {
+                    // only support a single branch in a template
+                    return;
+                }
+                val = {
+                    test: exprValue.test,
+                    ifTrue: val.value + exprValue.ifTrue,
+                    else: val.value + exprValue.else,
+                };
+            }
+            else {
+                // only support a single branch in a template
+                return;
+            }
+        }
+        if ('value' in val) {
+            val.value += node.quasis[i].value.cooked;
+        }
+        else {
+            val.ifTrue += node.quasis[i].value.cooked;
+            val.else += node.quasis[i].value.cooked;
+        }
+        return val;
+    },
+    ThisExpression: async function ThisExpression(_node, _walk) {
+        if (Object.hasOwnProperty.call(this.vars, 'this'))
+            return this.vars['this'];
+        return undefined;
+    },
+    UnaryExpression: async function UnaryExpression(node, walk) {
+        const val = await walk(node.argument);
+        if (!val)
+            return undefined;
+        if ('value' in val && 'wildcards' in val === false) {
+            if (node.operator === '+')
+                return { value: +val.value };
+            if (node.operator === '-')
+                return { value: -val.value };
+            if (node.operator === '~')
+                return { value: ~val.value };
+            if (node.operator === '!')
+                return { value: !val.value };
+        }
+        else if ('test' in val && 'wildcards' in val === false) {
+            if (node.operator === '+')
+                return { test: val.test, ifTrue: +val.ifTrue, else: +val.else };
+            if (node.operator === '-')
+                return { test: val.test, ifTrue: -val.ifTrue, else: -val.else };
+            if (node.operator === '~')
+                return { test: val.test, ifTrue: ~val.ifTrue, else: ~val.else };
+            if (node.operator === '!')
+                return { test: val.test, ifTrue: !val.ifTrue, else: !val.else };
+        }
+        return undefined;
+    },
+};
+visitors.LogicalExpression = visitors.BinaryExpression;