Fork channel

Create a new channel as a copy of main.

Rename channel

Rename main to:

Delete channel

Delete main? This cannot be undone.

error.test
# RUN: not %split-file %s %t 2>&1 | FileCheck %s
# RUN: not ls %t/dup

# CHECK: {{.*}}.test:[[#@LINE+1]]: error: empty part name
//--- 

# CHECK: {{.*}}.test:[[#@LINE+1]]: error: part name cannot have leading or trailing space
//---  leading_space

# CHECK: {{.*}}.test:[[#@LINE+1]]: error: part name cannot have leading or trailing space
//--- trailing_space 

;--- dup

# CHECK: {{.*}}.test:[[#@LINE+1]]: error: ';--- dup' occurs more than once
;--- dup