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classGrammarBuilder

packages/sql-parser/src/Grammar/GrammarBuilder.php:17

final class GrammarBuilder

Restricted visibility: declared "@visibility root". Code outside that scope must not name this declaration.

Collects the declarations of a grammar source and numbers them into a grammar.

Readers meet symbols in whatever order the source spells them, so names are gathered first and numbered only when the grammar is built: terminals in declaration order after the end marker, then the accept symbol and the nonterminals in the order their rules appear.

Constants§

public const ACCEPT = '$accept'

The name of the nonterminal the augmented start rule derives.

Methods§

public function terminal(string $name): void

Declares a terminal, keeping the position of its first declaration.

Parameters

$name string Terminal name

Test cases 30

Called from 10

public function nonterminal(string $name): void

Declares a nonterminal, keeping the position of its first declaration.

Parameters

$name string Nonterminal name

Test cases 1

GrammarBuilderTest::testNonterminal calls

Called from 1

method-call SqlParser\Grammar\GrammarBuilder::rule() packages/sql-parser/src/Grammar/GrammarBuilder.php:121

public function isTerminal(string $name): bool

Reports whether a name has been declared as a terminal.

Parameters

$name string Symbol name

Returns

bool True when the name is a terminal or a token class

Test cases 6

Called from 3

public function isNonterminal(string $name): bool

Reports whether a name has been declared as a nonterminal.

Parameters

$name string Symbol name

Returns

bool True when a rule derives the name

Test cases 3

GrammarBuilderTest::testIsNonterminal calls
GrammarBuilderTest::testNonterminal calls
GrammarBuilderTest::testTerminal calls

public function rule(
    string $lhs,
    list<string> $rhs,
    string|null $precedenceSymbol = null,
    bool $hidden = false,
): void

Records one production.

The left-hand side becomes a nonterminal; right-hand names are resolved when the grammar is built, so they may be declared later.

Parameters

`$lhs`	`string`	Nonterminal the rule derives
`$rhs`	`list<string>`	Symbol names the rule expands to
`$precedenceSymbol`	`string\|null`	Terminal named to lend its precedence
`$hidden`	`bool`	Whether the rule stands in for a mid-rule action

Test cases 40

Called from 3

Calls 1

method-call GrammarBuilder::nonterminal() line 121

public function precedence(list<string> $names, Associativity $associativity): void

Records one precedence declaration, ranking above every earlier one.

Parameters

`$names`	`list<string>`	Terminals the declaration ranks
`$associativity`	`Associativity`	How ties within the rank are settled

Test cases 5

Called from 2

Calls 2

method-call GrammarBuilder::terminal() line 135
new Precedence line 136

public function start(string $name): void

Names the start symbol; the first rule's left-hand side is used otherwise.

Parameters

$name string Nonterminal to start from

Test cases 1

GrammarBuilderTest::testStart calls

Called from 2

public function expect(int $count): void

Records how many shift/reduce conflicts the source declares as expected.

Parameters

$count int Declared conflict count

Test cases 1

GrammarBuilderTest::testExpect calls

Called from 1

method-call SqlParser\Compiler\BisonGrammarReader::declaration() packages/sql-parser/src/Compiler/BisonGrammarReader.php:110

public function policy(PrecedencePolicy $policy): void

Chooses how an unranked rule borrows its precedence.

Parameters

$policy PrecedencePolicy The generator's convention

Test cases 4

Called from 2

public function tokenClass(string $name, list<string> $members): void

Declares a token class, a terminal that stands for any of its members.

Parameters

`$name`	`string`	Class name
`$members`	`list<string>`	Terminals the class stands for

Test cases 3

Called from 2

Calls 1

method-call GrammarBuilder::terminal() line 179

public function fallback(string $target, list<string> $names): void

Declares which terminal to retry with when a listed terminal cannot be used.

Parameters

`$target`	`string`	Terminal to fall back to
`$names`	`list<string>`	Terminals that fall back

Test cases 1

GrammarBuilderTest::testFallback calls

Called from 1

method-call SqlParser\Compiler\LemonGrammarReader::declaration() packages/sql-parser/src/Compiler/LemonGrammarReader.php:99

Calls 1

method-call GrammarBuilder::terminal() line 192

public function wildcard(string $name): void

Declares the terminal that stands for any other.

Parameters

$name string Wildcard terminal name

Test cases 2

Called from 1

method-call SqlParser\Compiler\LemonGrammarReader::declaration() packages/sql-parser/src/Compiler/LemonGrammarReader.php:101

Calls 1

method-call GrammarBuilder::terminal() line 206

public function build(): Grammar

Numbers everything collected and answers the augmented grammar.

Returns

Grammar The grammar

Throws

GrammarException When no rule was recorded or a name is both a terminal and a nonterminal

UnknownSymbolException When a rule names a symbol nothing declares

Test cases 41

Called from 2

Calls 12

new GrammarException line 221
function-call array_keys line 223
method-call GrammarBuilder::isTerminal() line 224
new SymbolTable line 228
class-const SymbolTable::END() line 229
class-const GrammarBuilder::ACCEPT() line 230
method-call GrammarBuilder::firstVisibleLhs() line 232
new Rule line 233
method-call GrammarBuilder::id() line 233
method-call GrammarBuilder::numberedRules() line 234
function-call array_map line 243
new Grammar line 250

public function numberedRules(SymbolTable $symbols): list<Rule>

Numbers the recorded rules after the augmented start rule.

Parameters

$symbols SymbolTable The numbering

Returns

list<Rule> Rules numbered from one, alternatives counted per nonterminal

Throws

UnknownSymbolException When a rule names a symbol nothing declares

Test cases 1

GrammarBuilderTest::testNumberedRules calls

Called from 1

method-call SqlParser\Grammar\GrammarBuilder::build() packages/sql-parser/src/Grammar/GrammarBuilder.php:234

Calls 4

method-call GrammarBuilder::id() line 276
new Rule line 281
function-call count line 282
function-call array_map line 284

public function firstVisibleLhs(): string

Answers the left-hand side of the first rule that was not synthesised.

A rule synthesised for a mid-rule action is numbered before the rule it appears in, so the first recorded rule is not always the first rule the source wrote.

Returns

string Nonterminal of the first rule as written

Test cases 1

GrammarBuilderTest::testFirstVisibleLhs calls

Called from 1

method-call SqlParser\Grammar\GrammarBuilder::build() packages/sql-parser/src/Grammar/GrammarBuilder.php:232

public function id(SymbolTable $symbols, string $name): int

Resolves a name against the numbered symbols.

Parameters

`$symbols`	`SymbolTable`	The numbering
`$name`	`string`	Symbol name

Returns

int The symbol number

Throws

UnknownSymbolException When nothing declares the name

Test cases 2

Called from 8

Calls 2

method-call SymbolTable::id() line 326
new UnknownSymbolException line 328

Private surface 11§

Implementation details, listed for orientation only.

private array<string, true> $terminals = []

private array<string, true> $nonterminals = []

private list<array{string, list<string>, string|null, bool}> $rules = []

private array<string, Precedence> $precedences = []

private int $level = 0

private ?string $start = null

private ?int $expectedConflicts = null

private PrecedencePolicy $policy = PrecedencePolicy::LastTerminal

private array<string, list<string>> $tokenClasses = []

private array<string, string> $fallbacks = []

private ?string $wildcard = null

Test cases 48§

Test cases that cover or call this symbol, from the coverage report and from the analyzed test sources.

Dedicated tests 22

Other tests reaching this symbol 26

Relations§

Instantiated in 2

Method calls 23

Type declarations 5