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'use strict';
const fs = require('fs');const test = require('ava');
const Grammar = require('../src/Grammar');const ohm = require('..');
// --------------------------------------------------------------------// Tests// --------------------------------------------------------------------
test('action dictionary templates', t => {  const ns = ohm.grammars(`    G1 {      foo = bar      bar = baz baz baz      baz = qux      qux = quux "123"      quux = "42"      aaa = "duh"      bbb = ~aaa qux  -- blah    }    G2 <: G1 {      qux := "100"    }  `);  t.snapshot(ns.G1.toOperationActionDictionaryTemplate());  t.snapshot(ns.G2.toAttributeActionDictionaryTemplate());});
test('default start rule', t => {  let g = ohm.grammar('G {}');  t.is(g.defaultStartRule, undefined, 'undefined for an empty grammar');  t.throws(      () => {        g.match('a');      },      {message: /Missing start rule/},      'match throws with no start rule'  );  t.is(      Grammar.ProtoBuiltInRules.defaultStartRule,      undefined,      'undefined for ProtoBuiltInRules'  );  t.is(Grammar.BuiltInRules.defaultStartRule, undefined, 'undefined for BuiltInRules');
  const g2 = ohm.grammar('G2 <: G {}', {G: g});  t.is(g2.defaultStartRule, undefined, 'undefined for a subgrammar too');  t.throws(      () => {        g2.match('a');      },      {message: /Missing start rule/},      'match throws with no start rule'  );
  const ns = ohm.grammars('G { foo = "a" } G2 <: G {}');  t.is(ns.G.defaultStartRule, 'foo', 'only rule becomes default start rule');  t.is(ns.G2.defaultStartRule, 'foo', 'start rule is inherited from supergrammar');  t.is(ns.G.match('a').succeeded(), true, 'match works without a start rule argument');  t.is(ns.G2.match('a').succeeded(), true);
  const g3 = ohm.grammar('G3 <: G { bar = "b" }', ns);  t.is(g3.defaultStartRule, 'foo', 'start rule is still inherited');  t.is(g3.match('a').succeeded(), true);
  const g4 = ohm.grammar('G4 <: G3 { blah = "c" }', {G3: g3});  t.is(g4.defaultStartRule, 'foo', 'start rule inherited from super-supergrammar');  t.is(g4.match('a').succeeded(), true);
  g = ohm.grammar('G { digit += any }');  t.is(g.defaultStartRule, undefined, "extending alone doesn't set the start rule");  t.throws(      () => {        g.match('a');      },      {message: /Missing start rule/},      'match throws with no start rule'  );  g = ohm.grammar(`    G {      digit += any      blah = "3"    }  `);  t.is(g.defaultStartRule, 'blah', 'rule defined after extending becomes start rule');  t.is(g.match('3').succeeded(), true);
  g = ohm.grammar('G { digit := any }');  t.is(g.defaultStartRule, undefined, "overriding alone doesn't set the start rule");  t.throws(      () => {        g.match('a');      },      {message: /Missing start rule/},      'match throws with no start rule'  );  g = ohm.grammar(`    G {      digit := any      blah = "3"    }  `);  t.is(g.defaultStartRule, 'blah', 'rule defined after overriding becomes start rule');  t.is(g.match('3').succeeded(), true);
  g = ohm.grammar('G { x = "a"\n| -- nothing }');  t.is(g.defaultStartRule, 'x', "an inline rule doesn't become the default");
  // Test passing the default start rule as an argument to the Grammar constructor.  const root = Grammar.BuiltInRules;  t.throws(      () => {        new Grammar('G', root, {}, 'nonexistentRule'); // eslint-disable-line no-new      },      {message: /Invalid start rule/},      'throws when start rule is not in the grammar'  );  t.truthy(      new Grammar('G', root, {aRule: null}, 'aRule'),      'works when it is in the `rules` dict'  );  const rules = Object.create(root.rules);  t.truthy(new Grammar('G', root, rules, 'digit'), 'works when rule is in the supergrammar');});
test('grammar equality', t => {  const source = fs.readFileSync('test/arithmetic.ohm').toString();  const a = ohm.grammar(source);  const b = ohm.grammar(source);  t.is(a.equals(b), true, 'two grammars from same source');  t.is(a.equals(), false, 'comparing to undefined');  t.is(a.equals(null), false, 'comparing to null');
  const c = ohm.grammar(source.replace('digit', '(digit)'));  t.is(a.equals(c), true, 'still equal after meaningless source change');
  const {exp} = a.rules;  delete a.rules.exp;
  t.is(a.equals(b), false, 'not equal after deleting a rule');
  a.rules.exp = exp;  t.is(a.equals(b), true, 'equal aftering adding rule back');
  a.rules.exp.description = 'doyyy';  t.is(a.equals(b), false, 'not equal after changing a description');
  b.rules.zzz = {};  t.is(b.equals(c), false, 'not equal after adding additional rule');  delete b.rules.zzz;  t.is(b.equals(c), true);
  b.defaultStartRule = '';  t.is(b.equals(c), false, 'not equal after changing defaultStartRule');});