| The test directory contains tests of the Go tool chain and runtime. | 
 | It includes black box tests, regression tests, and error output tests. | 
 | They are run as part of all.bash. | 
 |  | 
 | To run just these tests, execute: | 
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 |     ../bin/go run run.go | 
 |  | 
 | To run just tests from specified files in this directory, execute: | 
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 |     ../bin/go run run.go -- file1.go file2.go ... | 
 |  | 
 | Standard library tests should be written as regular Go tests in the appropriate package. | 
 |  | 
 | The tool chain and runtime also have regular Go tests in their packages. | 
 | The main reasons to add a new test to this directory are: | 
 |  | 
 | * it is most naturally expressed using the test runner; or | 
 | * it is also applicable to `gccgo` and other Go tool chains. |