// from https://raw.githubusercontent.com/graphql/graphql-js/2fadef3f32bbe438d0e4c99db08858ecbbebf1d5/src/language/printer.ts
const { visit } = require('graphql');
const { printBlockString } = require('graphql/language/blockString')
/**
* Converts an AST into a string, using one set of reasonable
* formatting rules.
*/
module.exports = {
print(ast) {
return visit(ast, printDocASTReducer);
},
}
const MAX_LINE_LENGTH = 80;
const printDocASTReducer = {
Name: { leave: (node) => node.value },
Variable: { leave: (node) => '#x27; + node.name },
// Document
Document: {
leave: (node) => join(node.definitions, '\n\n'),
},
OperationDefinition: {
leave(node) {
let varDefs = wrap('(', join(node.variableDefinitions, ', '), ')');
if (varDefs.length > MAX_LINE_LENGTH) {
varDefs = wrap('(\n', indent(join(node.variableDefinitions, '\n')), '\n)');
}
const prefix = join([
node.operation,
join([node.name, varDefs]),
join(node.directives, ' '),
], ' ');
// Anonymous queries with no directives or variable definitions can use
// the query short form.
return (prefix === 'query' ? '' : prefix + ' ') + node.selectionSet;
},
},
VariableDefinition: {
leave: ({ variable, type, defaultValue, directives }) => variable +
': ' +
type +
wrap(' = ', defaultValue) +
wrap(' ', join(directives, ' ')),
},
SelectionSet: { leave: ({ selections }) => block(selections) },
Field: {
leave({ alias, name, arguments: args, directives, selectionSet }) {
const prefix = wrap('', alias, ': ') + name;
let argsLine = prefix + wrap('(', join(args, ', '), ')');
if (argsLine.length > MAX_LINE_LENGTH) {
argsLine = prefix + wrap('(\n', indent(join(args, '\n')), '\n)');
}
return join([argsLine, join(directives, ' '), selectionSet], ' ');
},
},
Argument: { leave: ({ name, value }) => name + ': ' + value },
// Fragments
FragmentSpread: {
leave: ({ name, directives }) => '...' + name + wrap(' ', join(directives, ' ')),
},
InlineFragment: {
leave: ({ typeCondition, directives, selectionSet }) => join([
'...',
wrap('on ', typeCondition),
join(directives, ' '),
selectionSet,
], ' '),
},
FragmentDefinition: {
leave: ({ name, typeCondition, variableDefinitions, directives, selectionSet, }) =>
// Note: fragment variable definitions are experimental and may be changed
// or removed in the future.
`fragment ${name}${wrap('(', join(variableDefinitions, ', '), ')')} ` +
`on ${typeCondition} ${wrap('', join(directives, ' '), ' ')}` +
selectionSet,
},
// Value
IntValue: { leave: ({ value }) => value },
FloatValue: { leave: ({ value }) => value },
StringValue: {
leave: ({ value, block: isBlockString }) => isBlockString ? printBlockString(value) : JSON.stringify(value),
},
BooleanValue: { leave: ({ value }) => (value ? 'true' : 'false') },
NullValue: { leave: () => 'null' },
EnumValue: { leave: ({ value }) => value },
ListValue: {
leave: ({ values }) => {
let line
let shouldWrap = hasMultilineItems(values)
if (!shouldWrap) {
line = '[' + join(values, ', ') + ']'
if (line.length > MAX_LINE_LENGTH) {
shouldWrap = true
}
}
if (shouldWrap) {
line = wrap('[\n', indent(join(values, ',\n')), '\n]')
}
return line
}
},
ObjectValue: {
leave: ({ fields }) => {
let line
let shouldWrap = hasMultilineItems(fields)
if (!shouldWrap) {
line = '{' + join(fields, ', ') + '}'
if (line.length > MAX_LINE_LENGTH) {
shouldWrap = true
}
}
if (shouldWrap) {
line = wrap('{\n', indent(join(fields, ',\n')), '\n}')
}
return line
}
},
ObjectField: { leave: ({ name, value }) => name + ': ' + value },
// Directive
Directive: {
leave: ({ name, arguments: args }) => '@' + name + wrap('(', join(args, ', '), ')'),
},
// Type
NamedType: { leave: ({ name }) => name },
ListType: { leave: ({ type }) => '[' + type + ']' },
NonNullType: { leave: ({ type }) => type + '!' },
// Type System Definitions
SchemaDefinition: {
leave: ({ description, directives, operationTypes }) => wrap('', description, '\n') +
join(['schema', join(directives, ' '), block(operationTypes)], ' '),
},
OperationTypeDefinition: {
leave: ({ operation, type }) => operation + ': ' + type,
},
ScalarTypeDefinition: {
leave: ({ description, name, directives }) => wrap('', description, '\n') +
join(['scalar', name, join(directives, ' ')], ' '),
},
ObjectTypeDefinition: {
leave: ({ description, name, interfaces, directives, fields }) => wrap('', description, '\n') +
join([
'type',
name,
wrap('implements ', join(interfaces, ' & ')),
join(directives, ' '),
block(fields),
], ' '),
},
FieldDefinition: {
leave: ({ description, name, arguments: args, type, directives }) => wrap('', description, '\n') +
name +
(hasMultilineItems(args)
? wrap('(\n', indent(join(args, '\n')), '\n)')
: wrap('(', join(args, ', '), ')')) +
': ' +
type +
wrap(' ', join(directives, ' ')),
},
InputValueDefinition: {
leave: ({ description, name, type, defaultValue, directives }) => wrap('', description, '\n') +
join([name + ': ' + type, wrap('= ', defaultValue), join(directives, ' ')], ' '),
},
InterfaceTypeDefinition: {
leave: ({ description, name, interfaces, directives, fields }) => wrap('', description, '\n') +
join([
'interface',
name,
wrap('implements ', join(interfaces, ' & ')),
join(directives, ' '),
block(fields),
], ' '),
},
UnionTypeDefinition: {
leave: ({ description, name, directives, types }) => wrap('', description, '\n') +
join(['union', name, join(directives, ' '), wrap('= ', join(types, ' | '))], ' '),
},
EnumTypeDefinition: {
leave: ({ description, name, directives, values }) => wrap('', description, '\n') +
join(['enum', name, join(directives, ' '), block(values)], ' '),
},
EnumValueDefinition: {
leave: ({ description, name, directives }) => wrap('', description, '\n') + join([name, join(directives, ' ')], ' '),
},
InputObjectTypeDefinition: {
leave: ({ description, name, directives, fields }) => wrap('', description, '\n') +
join(['input', name, join(directives, ' '), block(fields)], ' '),
},
DirectiveDefinition: {
leave: ({ description, name, arguments: args, repeatable, locations }) => wrap('', description, '\n') +
'directive @' +
name +
(hasMultilineItems(args)
? wrap('(\n', indent(join(args, '\n')), '\n)')
: wrap('(', join(args, ', '), ')')) +
(repeatable ? ' repeatable' : '') +
' on ' +
join(locations, ' | '),
},
SchemaExtension: {
leave: ({ directives, operationTypes }) => join(['extend schema', join(directives, ' '), block(operationTypes)], ' '),
},
ScalarTypeExtension: {
leave: ({ name, directives }) => join(['extend scalar', name, join(directives, ' ')], ' '),
},
ObjectTypeExtension: {
leave: ({ name, interfaces, directives, fields }) => join([
'extend type',
name,
wrap('implements ', join(interfaces, ' & ')),
join(directives, ' '),
block(fields),
], ' '),
},
InterfaceTypeExtension: {
leave: ({ name, interfaces, directives, fields }) => join([
'extend interface',
name,
wrap('implements ', join(interfaces, ' & ')),
join(directives, ' '),
block(fields),
], ' '),
},
UnionTypeExtension: {
leave: ({ name, directives, types }) => join([
'extend union',
name,
join(directives, ' '),
wrap('= ', join(types, ' | ')),
], ' '),
},
EnumTypeExtension: {
leave: ({ name, directives, values }) => join(['extend enum', name, join(directives, ' '), block(values)], ' '),
},
InputObjectTypeExtension: {
leave: ({ name, directives, fields }) => join(['extend input', name, join(directives, ' '), block(fields)], ' '),
},
};
/**
* Given maybeArray, print an empty string if it is null or empty, otherwise
* print all items together separated by separator if provided
*/
function join(maybeArray, separator = '') {
var _a;
return (_a = maybeArray === null || maybeArray === void 0 ? void 0 : maybeArray.filter((x) => x).join(separator)) !== null && _a !== void 0 ? _a : '';
}
/**
* Given array, print each item on its own line, wrapped in an
* indented "{ }" block.
*/
function block(array) {
return wrap('{\n', indent(join(array, '\n')), '\n}');
}
/**
* If maybeString is not null or empty, then wrap with start and end, otherwise print an empty string.
*/
function wrap(start, maybeString, end = '') {
return maybeString != null && maybeString !== ''
? start + maybeString + end
: '';
}
function indent(str) {
return wrap(' ', str.replace(/\n/g, '\n '));
}
function hasMultilineItems(maybeArray) {
var _a;
// istanbul ignore next (See: 'https://github.com/graphql/graphql-js/issues/2203')
return (_a = maybeArray === null || maybeArray === void 0 ? void 0 : maybeArray.some((str) => str.includes('\n'))) !== null && _a !== void 0 ? _a : false;
}
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