All files / src/compiler/phases/2-analyze/visitors/shared utils.js

99% Statements 199/201
98.68% Branches 75/76
100% Functions 7/7
98.98% Lines 196/198

Press n or j to go to the next uncovered block, b, p or k for the previous block.

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 1992x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 3066x 3066x 3066x 2124x 2124x 2124x 740x     740x 740x 1x 1x 740x 2123x 2124x 1x 1x 2124x 3050x 3050x 3050x 3050x 3050x 3050x 3057x 900x 900x 900x 3050x 3066x 36x 2x 2x 36x 3066x 2x 2x 2x 2x 2x 2x 2x 2x 4321x 66x 130x 130x 130x 130x 4321x 66x 104x 104x 104x 104x 4255x 3057x 3057x 3057x 3057x 3052x 3057x 23x 23x 23x 23x 23x 23x 23x 23x 23x 23x 23x 23x 23x 23x 23x 21x 23x 23x 23x 9x 23x 14x 14x 23x 3057x 4321x 2x 2x 2x 2x 2x 2x 2x 2x 2x 1402x 1x 1x 1x 1402x 2x 2x 2x 2x 2x 2x 4043x 2400x 2400x 4043x 6x 6x 4043x 2x 2x 2x 2x 2x 2x 8116x 8116x 8634x 8634x 8634x 7775x 8634x 1x 1x 1x 8634x 8115x 2x 2x 2x 2x 2x 2x 2x 2x 9357x 9357x 9357x 9357x 8831x 8831x 9357x 6873x 9306x 209x 209x 6664x 6664x 9282x 9357x 9357x 4747x 9357x 9357x 2x 2x 2x 2x 2x 2x 2x 3152x 12x 12x 3140x 3140x 3152x 3070x 3070x 3070x 3070x 3070x 2531x 2531x 2531x 2531x  
/** @import { AssignmentExpression, Expression, Pattern, PrivateIdentifier, Super, UpdateExpression, VariableDeclarator } from 'estree' */
/** @import { AST } from '#compiler' */
/** @import { AnalysisState, Context } from '../../types' */
/** @import { Scope } from '../../../scope' */
/** @import { NodeLike } from '../../../../errors.js' */
import * as e from '../../../../errors.js';
import { extract_identifiers, object } from '../../../../utils/ast.js';
import * as w from '../../../../warnings.js';
 
/**
 * @param {AssignmentExpression | UpdateExpression} node
 * @param {Pattern | Expression} argument
 * @param {AnalysisState} state
 */
export function validate_assignment(node, argument, state) {
	validate_no_const_assignment(node, argument, state.scope, false);
 
	if (argument.type === 'Identifier') {
		const binding = state.scope.get(argument.name);
 
		if (state.analysis.runes) {
			if (binding?.kind === 'derived') {
				e.constant_assignment(node, 'derived state');
			}
 
			if (binding?.kind === 'each') {
				e.each_item_invalid_assignment(node);
			}
		}
 
		if (binding?.kind === 'snippet') {
			e.snippet_parameter_assignment(node);
		}
	}
 
	let object = /** @type {Expression | Super} */ (argument);
 
	/** @type {Expression | PrivateIdentifier | null} */
	let property = null;
 
	while (object.type === 'MemberExpression') {
		property = object.property;
		object = object.object;
	}
 
	if (object.type === 'ThisExpression' && property?.type === 'PrivateIdentifier') {
		if (state.private_derived_state.includes(property.name)) {
			e.constant_assignment(node, 'derived state');
		}
	}
}
 
/**
 * @param {NodeLike} node
 * @param {Pattern | Expression} argument
 * @param {Scope} scope
 * @param {boolean} is_binding
 */
export function validate_no_const_assignment(node, argument, scope, is_binding) {
	if (argument.type === 'ArrayPattern') {
		for (const element of argument.elements) {
			if (element) {
				validate_no_const_assignment(node, element, scope, is_binding);
			}
		}
	} else if (argument.type === 'ObjectPattern') {
		for (const element of argument.properties) {
			if (element.type === 'Property') {
				validate_no_const_assignment(node, element.value, scope, is_binding);
			}
		}
	} else if (argument.type === 'Identifier') {
		const binding = scope.get(argument.name);
		if (
			binding?.kind === 'derived' ||
			binding?.declaration_kind === 'import' ||
			(binding?.declaration_kind === 'const' && binding.kind !== 'each')
		) {
			// e.invalid_const_assignment(
			// 	node,
			// 	is_binding,
			// 	// This takes advantage of the fact that we don't assign initial for let directives and then/catch variables.
			// 	// If we start doing that, we need another property on the binding to differentiate, or give up on the more precise error message.
			// 	binding.kind !== 'state' &&
			// 		binding.kind !== 'raw_state' &&
			// 		(binding.kind !== 'normal' || !binding.initial)
			// );
 
			// TODO have a more specific error message for assignments to things like `{:then foo}`
			const thing =
				binding.declaration_kind === 'import'
					? 'import'
					: binding.kind === 'derived'
						? 'derived state'
						: 'constant';
 
			if (is_binding) {
				e.constant_binding(node, thing);
			} else {
				e.constant_assignment(node, thing);
			}
		}
	}
}
 
/**
 * Validates that the opening of a control flow block is `{` immediately followed by the expected character.
 * In legacy mode whitespace is allowed inbetween. TODO remove once legacy mode is gone and move this into parser instead.
 * @param {{start: number; end: number}} node
 * @param {AnalysisState} state
 * @param {string} expected
 */
export function validate_opening_tag(node, state, expected) {
	if (state.analysis.source[node.start + 1] !== expected) {
		// avoid a sea of red and only mark the first few characters
		e.block_unexpected_character({ start: node.start, end: node.start + 5 }, expected);
	}
}
 
/**
 * @param {AST.Fragment | null | undefined} node
 * @param {Context} context
 */
export function validate_block_not_empty(node, context) {
	if (!node) return;
	// Assumption: If the block has zero elements, someone's in the middle of typing it out,
	// so don't warn in that case because it would be distracting.
	if (node.nodes.length === 1 && node.nodes[0].type === 'Text' && !node.nodes[0].raw.trim()) {
		w.block_empty(node.nodes[0]);
	}
}
 
/**
 * @param {VariableDeclarator} node
 * @param {AnalysisState} state
 */
export function ensure_no_module_import_conflict(node, state) {
	const ids = extract_identifiers(node.id);
	for (const id of ids) {
		if (
			state.ast_type === 'instance' &&
			state.scope === state.analysis.instance.scope &&
			state.analysis.module.scope.get(id.name)?.declaration_kind === 'import'
		) {
			// TODO fix the message here
			e.declaration_duplicate_module_import(node.id);
		}
	}
}
 
/**
 * A 'safe' identifier means that the `foo` in `foo.bar` or `foo()` will not
 * call functions that require component context to exist
 * @param {Expression | Super} expression
 * @param {Scope} scope
 */
export function is_safe_identifier(expression, scope) {
	let node = expression;
	while (node.type === 'MemberExpression') node = node.object;
 
	if (node.type !== 'Identifier') return false;
 
	const binding = scope.get(node.name);
	if (!binding) return true;
 
	if (binding.kind === 'store_sub') {
		return is_safe_identifier({ name: node.name.slice(1), type: 'Identifier' }, scope);
	}
 
	return (
		binding.declaration_kind !== 'import' &&
		binding.kind !== 'prop' &&
		binding.kind !== 'bindable_prop' &&
		binding.kind !== 'rest_prop'
	);
}
 
/**
 * @param {Expression | Super} node
 * @param {Context} context
 * @returns {boolean}
 */
export function is_pure(node, context) {
	if (node.type !== 'Identifier' && node.type !== 'MemberExpression') {
		return false;
	}
 
	const left = object(node);
	if (!left) return false;
 
	if (left.type === 'Identifier') {
		const binding = context.state.scope.get(left.name);
		if (binding === null) return true; // globals are assumed to be safe
	}
 
	// TODO add more cases (safe Svelte imports, etc)
	return false;
}