WordPress/Sniffs/WP/CronIntervalSniff.php
public function process_token( $stackPtr ) {
		$token = $this->tokens[ $stackPtr ];

		if ( 'cron_schedules' !== $this->strip_quotes( $token['content'] ) ) {
			return;
		}

		// If within add_filter.
		$functionPtr = $this->is_in_function_call( $stackPtr, $this->valid_functions );
		if ( false === $functionPtr ) {
			return;
		}

		$callback = $this->get_function_call_parameter( $functionPtr, 2 );
		if ( false === $callback ) {
			return;
		}

		if ( $stackPtr >= $callback['start'] ) {
			// "cron_schedules" found in the second parameter, not the first.
			return;
		}

		// Detect callback function name.
		$callbackArrayPtr = $this->phpcsFile->findNext( Tokens::$emptyTokens, $callback['start'], ( $callback['end'] + 1 ), true );

		// If callback is array, get second element.
		if ( false !== $callbackArrayPtr
			&& ( \T_ARRAY === $this->tokens[ $callbackArrayPtr ]['code']
				|| \T_OPEN_SHORT_ARRAY === $this->tokens[ $callbackArrayPtr ]['code'] )
		) {
			$callback = $this->get_function_call_parameter( $callbackArrayPtr, 2 );

			if ( false === $callback ) {
				$this->confused( $stackPtr );
				return;
			}
		}

		unset( $functionPtr );

		// Search for the function in tokens.
		$callbackFunctionPtr = $this->phpcsFile->findNext( array( \T_CONSTANT_ENCAPSED_STRING, \T_DOUBLE_QUOTED_STRING, \T_CLOSURE ), $callback['start'], ( $callback['end'] + 1 ) );

		if ( false === $callbackFunctionPtr ) {
			$this->confused( $stackPtr );
			return;
		}

		if ( \T_CLOSURE === $this->tokens[ $callbackFunctionPtr ]['code'] ) {
			$functionPtr = $callbackFunctionPtr;
		} else {
			$functionName = $this->strip_quotes( $this->tokens[ $callbackFunctionPtr ]['content'] );

			for ( $ptr = 0; $ptr < $this->phpcsFile->numTokens; $ptr++ ) {
				if ( \T_FUNCTION === $this->tokens[ $ptr ]['code'] ) {
					$foundName = $this->phpcsFile->getDeclarationName( $ptr );
					if ( $foundName === $functionName ) {
						$functionPtr = $ptr;
						break;
					} elseif ( isset( $this->tokens[ $ptr ]['scope_closer'] ) ) {
						// Skip to the end of the function definition.
						$ptr = $this->tokens[ $ptr ]['scope_closer'];
					}
				}
			}
		}

		if ( ! isset( $functionPtr ) ) {
			$this->confused( $stackPtr );
			return;
		}

		if ( ! isset( $this->tokens[ $functionPtr ]['scope_opener'], $this->tokens[ $functionPtr ]['scope_closer'] ) ) {
			return;
		}

		$opening = $this->tokens[ $functionPtr ]['scope_opener'];
		$closing = $this->tokens[ $functionPtr ]['scope_closer'];
		for ( $i = $opening; $i <= $closing; $i++ ) {

			if ( \in_array( $this->tokens[ $i ]['code'], array( \T_CONSTANT_ENCAPSED_STRING, \T_DOUBLE_QUOTED_STRING ), true ) ) {
				if ( 'interval' === $this->strip_quotes( $this->tokens[ $i ]['content'] ) ) {
					$operator = $this->phpcsFile->findNext( \T_DOUBLE_ARROW, $i, null, false, null, true );
					if ( false === $operator ) {
						$this->confused( $stackPtr );
						return;
					}

					$valueStart = $this->phpcsFile->findNext( Tokens::$emptyTokens, ( $operator + 1 ), null, true, null, true );
					$valueEnd   = $this->phpcsFile->findNext( array( \T_COMMA, \T_CLOSE_PARENTHESIS ), ( $valueStart + 1 ) );
					$value      = '';
					for ( $j = $valueStart; $j < $valueEnd; $j++ ) {
						if ( isset( Tokens::$emptyTokens[ $this->tokens[ $j ]['code'] ] ) ) {
							continue;
						}
						$value .= $this->tokens[ $j ]['content'];
					}

					if ( is_numeric( $value ) ) {
						$interval = $value;
						break;
					}

					// Deal correctly with WP time constants.
					$value = str_replace( array_keys( $this->wp_time_constants ), array_values( $this->wp_time_constants ), $value );

					// If all digits and operators, eval!
					if ( preg_match( '#^[\s\d+*/-]+$#', $value ) > 0 ) {
						$interval = eval( "return ( $value );" ); // phpcs:ignore Squiz.PHP.Eval -- No harm here.
						break;
					}

					$this->confused( $stackPtr );
					return;
				}
			}
		}

		$this->min_interval = (int) $this->min_interval;

		if ( isset( $interval ) && $interval < $this->min_interval ) {
			$minutes = round( ( $this->min_interval / 60 ), 1 );
			$this->phpcsFile->addWarning(
				'Scheduling crons at %s sec ( less than %s minutes ) is discouraged.',
				$stackPtr,
				'CronSchedulesInterval',
				array(
					$interval,
					$minutes,
				)
			);
			return;
		}
	}
public function process_token( $stackPtr ) {
		$token = $this->tokens[ $stackPtr ];

		if ( 'cron_schedules' !== $this->strip_quotes( $token['content'] ) ) {
			return;
		}

		// If within add_filter.
		$functionPtr = $this->is_in_function_call( $stackPtr, $this->valid_functions );
		if ( false === $functionPtr ) {
			return;
		}

		$callback = $this->get_function_call_parameter( $functionPtr, 2 );
		if ( false === $callback ) {
			return;
		}

		if ( $stackPtr >= $callback['start'] ) {
			// "cron_schedules" found in the second parameter, not the first.
			return;
		}

		// Detect callback function name.
		$callbackArrayPtr = $this->phpcsFile->findNext( Tokens::$emptyTokens, $callback['start'], ( $callback['end'] + 1 ), true );

		// If callback is array, get second element.
		if ( false !== $callbackArrayPtr
			&& ( \T_ARRAY === $this->tokens[ $callbackArrayPtr ]['code']
				|| \T_OPEN_SHORT_ARRAY === $this->tokens[ $callbackArrayPtr ]['code'] )
		) {
			$callback = $this->get_function_call_parameter( $callbackArrayPtr, 2 );

			if ( false === $callback ) {
				$this->confused( $stackPtr );
				return;
			}
		}

		unset( $functionPtr );

		// Search for the function in tokens.
		$callbackFunctionPtr = $this->phpcsFile->findNext( array( \T_CONSTANT_ENCAPSED_STRING, \T_DOUBLE_QUOTED_STRING, \T_CLOSURE ), $callback['start'], ( $callback['end'] + 1 ) );

		if ( false === $callbackFunctionPtr ) {
			$this->confused( $stackPtr );
			return;
		}

		if ( \T_CLOSURE === $this->tokens[ $callbackFunctionPtr ]['code'] ) {
			$functionPtr = $callbackFunctionPtr;
		} else {
			$functionName = $this->strip_quotes( $this->tokens[ $callbackFunctionPtr ]['content'] );

			for ( $ptr = 0; $ptr < $this->phpcsFile->numTokens; $ptr++ ) {
				if ( \T_FUNCTION === $this->tokens[ $ptr ]['code'] ) {
					$foundName = $this->phpcsFile->getDeclarationName( $ptr );
					if ( $foundName === $functionName ) {
						$functionPtr = $ptr;
						break;
					} elseif ( isset( $this->tokens[ $ptr ]['scope_closer'] ) ) {
						// Skip to the end of the function definition.
						$ptr = $this->tokens[ $ptr ]['scope_closer'];
					}
				}
			}
		}

		if ( ! isset( $functionPtr ) ) {
			$this->confused( $stackPtr );
			return;
		}

		if ( ! isset( $this->tokens[ $functionPtr ]['scope_opener'], $this->tokens[ $functionPtr ]['scope_closer'] ) ) {
			return;
		}

		$opening = $this->tokens[ $functionPtr ]['scope_opener'];
		$closing = $this->tokens[ $functionPtr ]['scope_closer'];
		for ( $i = $opening; $i <= $closing; $i++ ) {

			if ( \in_array( $this->tokens[ $i ]['code'], array( \T_CONSTANT_ENCAPSED_STRING, \T_DOUBLE_QUOTED_STRING ), true ) ) {
				if ( 'interval' === $this->strip_quotes( $this->tokens[ $i ]['content'] ) ) {
					$operator = $this->phpcsFile->findNext( \T_DOUBLE_ARROW, $i, null, false, null, true );
					if ( false === $operator ) {
						$this->confused( $stackPtr );
						return;
					}

					$valueStart = $this->phpcsFile->findNext( Tokens::$emptyTokens, ( $operator + 1 ), null, true, null, true );
					$valueEnd   = $this->phpcsFile->findNext( array( \T_COMMA, \T_CLOSE_PARENTHESIS ), ( $valueStart + 1 ) );
					$value      = '';
					for ( $j = $valueStart; $j < $valueEnd; $j++ ) {
						if ( isset( Tokens::$emptyTokens[ $this->tokens[ $j ]['code'] ] ) ) {
							continue;
						}
						$value .= $this->tokens[ $j ]['content'];
					}

					if ( is_numeric( $value ) ) {
						$interval = $value;
						break;
					}

					// Deal correctly with WP time constants.
					$value = str_replace( array_keys( $this->wp_time_constants ), array_values( $this->wp_time_constants ), $value );

					// If all digits and operators, eval!
					if ( preg_match( '#^[\s\d+*/-]+$#', $value ) > 0 ) {
						$interval = eval( "return ( $value );" ); // phpcs:ignore Squiz.PHP.Eval -- No harm here.
						break;
					}

					$this->confused( $stackPtr );
					return;
				}
			}
		}

		$this->min_interval = (int) $this->min_interval;

		if ( isset( $interval ) && $interval < $this->min_interval ) {
			$minutes = round( ( $this->min_interval / 60 ), 1 );
			$this->phpcsFile->addWarning(
				'Scheduling crons at %s sec ( less than %s minutes ) is discouraged.',
				$stackPtr,
				'CronSchedulesInterval',
				array(
					$interval,
					$minutes,
				)
			);
			return;
		}
	}
Processes this test, when one of its tokens is encountered.

@param int $stackPtr The position of the current token in the stack.

@return void