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author | Minteck <contact@minteck.org> | 2022-11-28 17:31:34 +0100 |
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committer | Minteck <contact@minteck.org> | 2022-11-28 17:31:34 +0100 |
commit | 7923aa8942b55884320ef2428417e3ee4b121613 (patch) | |
tree | 7993632f2898b1998f25b11ce40a8d2eb3d44730 /MistyCore/node_modules/yaml/dist/visit.js | |
download | mistyos-og-7923aa8942b55884320ef2428417e3ee4b121613.tar.gz mistyos-og-7923aa8942b55884320ef2428417e3ee4b121613.tar.bz2 mistyos-og-7923aa8942b55884320ef2428417e3ee4b121613.zip |
Diffstat (limited to 'MistyCore/node_modules/yaml/dist/visit.js')
-rw-r--r-- | MistyCore/node_modules/yaml/dist/visit.js | 236 |
1 files changed, 236 insertions, 0 deletions
diff --git a/MistyCore/node_modules/yaml/dist/visit.js b/MistyCore/node_modules/yaml/dist/visit.js new file mode 100644 index 0000000..1f3db46 --- /dev/null +++ b/MistyCore/node_modules/yaml/dist/visit.js @@ -0,0 +1,236 @@ +'use strict'; + +var Node = require('./nodes/Node.js'); + +const BREAK = Symbol('break visit'); +const SKIP = Symbol('skip children'); +const REMOVE = Symbol('remove node'); +/** + * Apply a visitor to an AST node or document. + * + * Walks through the tree (depth-first) starting from `node`, calling a + * `visitor` function with three arguments: + * - `key`: For sequence values and map `Pair`, the node's index in the + * collection. Within a `Pair`, `'key'` or `'value'`, correspondingly. + * `null` for the root node. + * - `node`: The current node. + * - `path`: The ancestry of the current node. + * + * The return value of the visitor may be used to control the traversal: + * - `undefined` (default): Do nothing and continue + * - `visit.SKIP`: Do not visit the children of this node, continue with next + * sibling + * - `visit.BREAK`: Terminate traversal completely + * - `visit.REMOVE`: Remove the current node, then continue with the next one + * - `Node`: Replace the current node, then continue by visiting it + * - `number`: While iterating the items of a sequence or map, set the index + * of the next step. This is useful especially if the index of the current + * node has changed. + * + * If `visitor` is a single function, it will be called with all values + * encountered in the tree, including e.g. `null` values. Alternatively, + * separate visitor functions may be defined for each `Map`, `Pair`, `Seq`, + * `Alias` and `Scalar` node. To define the same visitor function for more than + * one node type, use the `Collection` (map and seq), `Value` (map, seq & scalar) + * and `Node` (alias, map, seq & scalar) targets. Of all these, only the most + * specific defined one will be used for each node. + */ +function visit(node, visitor) { + const visitor_ = initVisitor(visitor); + if (Node.isDocument(node)) { + const cd = visit_(null, node.contents, visitor_, Object.freeze([node])); + if (cd === REMOVE) + node.contents = null; + } + else + visit_(null, node, visitor_, Object.freeze([])); +} +// Without the `as symbol` casts, TS declares these in the `visit` +// namespace using `var`, but then complains about that because +// `unique symbol` must be `const`. +/** Terminate visit traversal completely */ +visit.BREAK = BREAK; +/** Do not visit the children of the current node */ +visit.SKIP = SKIP; +/** Remove the current node */ +visit.REMOVE = REMOVE; +function visit_(key, node, visitor, path) { + const ctrl = callVisitor(key, node, visitor, path); + if (Node.isNode(ctrl) || Node.isPair(ctrl)) { + replaceNode(key, path, ctrl); + return visit_(key, ctrl, visitor, path); + } + if (typeof ctrl !== 'symbol') { + if (Node.isCollection(node)) { + path = Object.freeze(path.concat(node)); + for (let i = 0; i < node.items.length; ++i) { + const ci = visit_(i, node.items[i], visitor, path); + if (typeof ci === 'number') + i = ci - 1; + else if (ci === BREAK) + return BREAK; + else if (ci === REMOVE) { + node.items.splice(i, 1); + i -= 1; + } + } + } + else if (Node.isPair(node)) { + path = Object.freeze(path.concat(node)); + const ck = visit_('key', node.key, visitor, path); + if (ck === BREAK) + return BREAK; + else if (ck === REMOVE) + node.key = null; + const cv = visit_('value', node.value, visitor, path); + if (cv === BREAK) + return BREAK; + else if (cv === REMOVE) + node.value = null; + } + } + return ctrl; +} +/** + * Apply an async visitor to an AST node or document. + * + * Walks through the tree (depth-first) starting from `node`, calling a + * `visitor` function with three arguments: + * - `key`: For sequence values and map `Pair`, the node's index in the + * collection. Within a `Pair`, `'key'` or `'value'`, correspondingly. + * `null` for the root node. + * - `node`: The current node. + * - `path`: The ancestry of the current node. + * + * The return value of the visitor may be used to control the traversal: + * - `Promise`: Must resolve to one of the following values + * - `undefined` (default): Do nothing and continue + * - `visit.SKIP`: Do not visit the children of this node, continue with next + * sibling + * - `visit.BREAK`: Terminate traversal completely + * - `visit.REMOVE`: Remove the current node, then continue with the next one + * - `Node`: Replace the current node, then continue by visiting it + * - `number`: While iterating the items of a sequence or map, set the index + * of the next step. This is useful especially if the index of the current + * node has changed. + * + * If `visitor` is a single function, it will be called with all values + * encountered in the tree, including e.g. `null` values. Alternatively, + * separate visitor functions may be defined for each `Map`, `Pair`, `Seq`, + * `Alias` and `Scalar` node. To define the same visitor function for more than + * one node type, use the `Collection` (map and seq), `Value` (map, seq & scalar) + * and `Node` (alias, map, seq & scalar) targets. Of all these, only the most + * specific defined one will be used for each node. + */ +async function visitAsync(node, visitor) { + const visitor_ = initVisitor(visitor); + if (Node.isDocument(node)) { + const cd = await visitAsync_(null, node.contents, visitor_, Object.freeze([node])); + if (cd === REMOVE) + node.contents = null; + } + else + await visitAsync_(null, node, visitor_, Object.freeze([])); +} +// Without the `as symbol` casts, TS declares these in the `visit` +// namespace using `var`, but then complains about that because +// `unique symbol` must be `const`. +/** Terminate visit traversal completely */ +visitAsync.BREAK = BREAK; +/** Do not visit the children of the current node */ +visitAsync.SKIP = SKIP; +/** Remove the current node */ +visitAsync.REMOVE = REMOVE; +async function visitAsync_(key, node, visitor, path) { + const ctrl = await callVisitor(key, node, visitor, path); + if (Node.isNode(ctrl) || Node.isPair(ctrl)) { + replaceNode(key, path, ctrl); + return visitAsync_(key, ctrl, visitor, path); + } + if (typeof ctrl !== 'symbol') { + if (Node.isCollection(node)) { + path = Object.freeze(path.concat(node)); + for (let i = 0; i < node.items.length; ++i) { + const ci = await visitAsync_(i, node.items[i], visitor, path); + if (typeof ci === 'number') + i = ci - 1; + else if (ci === BREAK) + return BREAK; + else if (ci === REMOVE) { + node.items.splice(i, 1); + i -= 1; + } + } + } + else if (Node.isPair(node)) { + path = Object.freeze(path.concat(node)); + const ck = await visitAsync_('key', node.key, visitor, path); + if (ck === BREAK) + return BREAK; + else if (ck === REMOVE) + node.key = null; + const cv = await visitAsync_('value', node.value, visitor, path); + if (cv === BREAK) + return BREAK; + else if (cv === REMOVE) + node.value = null; + } + } + return ctrl; +} +function initVisitor(visitor) { + if (typeof visitor === 'object' && + (visitor.Collection || visitor.Node || visitor.Value)) { + return Object.assign({ + Alias: visitor.Node, + Map: visitor.Node, + Scalar: visitor.Node, + Seq: visitor.Node + }, visitor.Value && { + Map: visitor.Value, + Scalar: visitor.Value, + Seq: visitor.Value + }, visitor.Collection && { + Map: visitor.Collection, + Seq: visitor.Collection + }, visitor); + } + return visitor; +} +function callVisitor(key, node, visitor, path) { + if (typeof visitor === 'function') + return visitor(key, node, path); + if (Node.isMap(node)) + return visitor.Map?.(key, node, path); + if (Node.isSeq(node)) + return visitor.Seq?.(key, node, path); + if (Node.isPair(node)) + return visitor.Pair?.(key, node, path); + if (Node.isScalar(node)) + return visitor.Scalar?.(key, node, path); + if (Node.isAlias(node)) + return visitor.Alias?.(key, node, path); + return undefined; +} +function replaceNode(key, path, node) { + const parent = path[path.length - 1]; + if (Node.isCollection(parent)) { + parent.items[key] = node; + } + else if (Node.isPair(parent)) { + if (key === 'key') + parent.key = node; + else + parent.value = node; + } + else if (Node.isDocument(parent)) { + parent.contents = node; + } + else { + const pt = Node.isAlias(parent) ? 'alias' : 'scalar'; + throw new Error(`Cannot replace node with ${pt} parent`); + } +} + +exports.visit = visit; +exports.visitAsync = visitAsync; |