Detect nesting it and pending at run-time

spec/std/array_spec.cr

@@ -1096,7 +1096,7 @@ describe "Array" do
 
   describe "to_s" do
     it "does to_s" do
-      it { [1, 2, 3].to_s.should eq("[1, 2, 3]") }
+      [1, 2, 3].to_s.should eq("[1, 2, 3]")
     end
 
     it "does with recursive" do

spec/std/char_spec.cr

@@ -373,10 +373,10 @@ describe "Char" do
   end
 
   it "does number?" do
-    it { '1'.number?.should be_true }
-    it { '٠'.number?.should be_true }
-    it { '٢'.number?.should be_true }
-    it { 'a'.number?.should be_false }
+    '1'.number?.should be_true
+    '٠'.number?.should be_true
+    '٢'.number?.should be_true
+    'a'.number?.should be_false
   end
 
   it "does ascii_control?" do

spec/std/deque_spec.cr

@@ -545,7 +545,7 @@ describe "Deque" do
 
   describe "to_s" do
     it "does to_s" do
-      it { Deque{1, 2, 3}.to_s.should eq("Deque{1, 2, 3}") }
+      Deque{1, 2, 3}.to_s.should eq("Deque{1, 2, 3}")
     end
 
     it "does with recursive" do

spec/std/float_spec.cr

@@ -14,7 +14,7 @@ describe "Float" do
 
   describe "%" do
     it "uses modulo behavior, not remainder behavior" do
-      it { ((-11.5) % 4.0).should eq(0.5) }
+      ((-11.5) % 4.0).should eq(0.5)
     end
   end
 

spec/std/spec_spec.cr

@@ -114,6 +114,18 @@ describe "Spec matchers" do
       true.should be_truthy
     end
   end
+
+  it "detects a nesting `it`" do
+    ex = expect_raises(Spec::NestingSpecError) { it { } }
+    ex.message.should eq "can't nest `it` or `pending`"
+    ex.file.should eq __FILE__
+  end
+
+  it "detects a nesting `pending`" do
+    ex = expect_raises(Spec::NestingSpecError) { pending }
+    ex.message.should eq "can't nest `it` or `pending`"
+    ex.file.should eq __FILE__
+  end
 end
 
 describe "Spec" do

src/spec/context.cr

@@ -81,21 +81,21 @@ module Spec
             puts
             puts "#{(i + 1).to_s.rjust(3, ' ')}) #{fail.description}"
 
-            if ex.is_a?(AssertionFailed)
+            if ex.is_a?(SpecError)
               source_line = Spec.read_line(ex.file, ex.line)
               if source_line
                 puts Spec.color("     Failure/Error: #{source_line.strip}", :error)
               end
             end
             puts
 
-            message = ex.is_a?(AssertionFailed) ? ex.to_s : ex.inspect_with_backtrace
+            message = ex.is_a?(SpecError) ? ex.to_s : ex.inspect_with_backtrace
             message.split('\n').each do |line|
               print "       "
               puts Spec.color(line, :error)
             end
 
-            if ex.is_a?(AssertionFailed)
+            if ex.is_a?(SpecError)
               puts
               puts Spec.color("     # #{Spec.relative_file(ex.file)}:#{ex.line}", :comment)
             end
@@ -166,6 +166,19 @@ module Spec
     def matches?(pattern, line, locations)
       false
     end
+
+    @@spec_nesting = false
+
+    def self.check_nesting_spec(file, line, &block)
+      raise NestingSpecError.new("can't nest `it` or `pending`", file, line) if @@spec_nesting
+
+      @@spec_nesting = true
+      begin
+        yield
+      ensure
+        @@spec_nesting = false
+      end
+    end
   end
 
   # :nodoc:

src/spec/dsl.cr

@@ -38,7 +38,7 @@ module Spec
   end
 
   # :nodoc:
-  class AssertionFailed < Exception
+  class SpecError < Exception
     getter file : String
     getter line : Int32
 
@@ -47,6 +47,14 @@ module Spec
     end
   end
 
+  # :nodoc:
+  class AssertionFailed < SpecError
+  end
+
+  # :nodoc:
+  class NestingSpecError < SpecError
+  end
+
   @@aborted = false
 
   # :nodoc:

src/spec/expectations.cr

@@ -385,6 +385,11 @@ module Spec
         raise ex
       end
 
+      # `NestingSpecError` is treated as the same above.
+      if ex.is_a?(Spec::NestingSpecError) && klass != Spec::NestingSpecError
+        raise ex
+      end
+
       ex_to_s = ex.to_s
       case message
       when Regex

src/spec/methods.cr

@@ -36,23 +36,25 @@ module Spec::Methods
   #
   # It is usually used inside a `#describe` or `#context` section.
   def it(description = "assert", file = __FILE__, line = __LINE__, end_line = __END_LINE__, &block)
-    return unless Spec.matches?(description, file, line, end_line)
+    Spec::RootContext.check_nesting_spec(file, line) do
+      return unless Spec.matches?(description, file, line, end_line)
 
-    Spec.formatters.each(&.before_example(description))
+      Spec.formatters.each(&.before_example(description))
 
-    start = Time.monotonic
-    begin
-      Spec.run_before_each_hooks
-      block.call
-      Spec::RootContext.report(:success, description, file, line, Time.monotonic - start)
-    rescue ex : Spec::AssertionFailed
-      Spec::RootContext.report(:fail, description, file, line, Time.monotonic - start, ex)
-      Spec.abort! if Spec.fail_fast?
-    rescue ex
-      Spec::RootContext.report(:error, description, file, line, Time.monotonic - start, ex)
-      Spec.abort! if Spec.fail_fast?
-    ensure
-      Spec.run_after_each_hooks
+      start = Time.monotonic
+      begin
+        Spec.run_before_each_hooks
+        block.call
+        Spec::RootContext.report(:success, description, file, line, Time.monotonic - start)
+      rescue ex : Spec::AssertionFailed
+        Spec::RootContext.report(:fail, description, file, line, Time.monotonic - start, ex)
+        Spec.abort! if Spec.fail_fast?
+      rescue ex
+        Spec::RootContext.report(:error, description, file, line, Time.monotonic - start, ex)
+        Spec.abort! if Spec.fail_fast?
+      ensure
+        Spec.run_after_each_hooks
+      end
     end
   end
 
@@ -68,11 +70,13 @@ module Spec::Methods
   #
   # It is usually used inside a `#describe` or `#context` section.
   def pending(description = "assert", file = __FILE__, line = __LINE__, end_line = __END_LINE__, &block)
-    return unless Spec.matches?(description, file, line, end_line)
+    Spec::RootContext.check_nesting_spec(file, line) do
+      return unless Spec.matches?(description, file, line, end_line)
 
-    Spec.formatters.each(&.before_example(description))
+      Spec.formatters.each(&.before_example(description))
 
-    Spec::RootContext.report(:pending, description, file, line)
+      Spec::RootContext.report(:pending, description, file, line)
+    end
   end
 
   # Defines a yet-to-be-implemented pending test case