c_extensions/c_tracepoints_no_parens.rb

tests/_examples/c_extensions/c_tracepoints_no_parens.rb in the metorex repository.

# A C extension making a TracePoint whose hook is a C function, and turning
# TracePoints on and off.
require "tmpdir"
require_relative "build_helper"

def traced
  1
end

directory = Dir.mktmpdir
require build_extension("c_tracepoints.c", "c_tracepoints", directory)
tracepoints = CTracepoints.new

seen = []
calls = tracepoints.trace_new CTracepoints::CALL | CTracepoints::RETURN, seen
p calls.class
p calls.enabled?
p tracepoints.enable calls
traced
p tracepoints.disable calls
traced
p seen

lines = []
line_trace = tracepoints.trace_new CTracepoints::LINE, lines
line_trace.enable
total = 1 + 1
line_trace.disable
p lines.uniq

nothing = []
silent = tracepoints.trace_new CTracepoints::NONE, nothing
silent.enable
traced
silent.disable
p nothing

FileUtils.rm_rf directory

Output:

TracePoint
false
true
false
[:call, :return]
[:line]
[]