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Hide Undefined Constant

Hiding a constant that is already undefined is a no-op. This can be useful when a spec file may run in either an isolated environment (e.g. when running one spec file) or in a full environment with all parts of your code base loaded (e.g. when running your entire suite).

Hiding undefined constant​

Given a file named "hide_const_spec.rb" with:

RSpec.describe "hiding UNDEFINED_CONSTANT" do
  it "has no effect" do
    hide_const("UNDEFINED_CONSTANT")
    expect { UNDEFINED_CONSTANT }.to raise_error(NameError)
  end

  it "is still undefined after the example completes" do
    expect { UNDEFINED_CONSTANT }.to raise_error(NameError)
  end
end

When I run rspec hide_const_spec.rb

Then the examples should all pass.