Introduce practical test section

1 files changed, 23 insertions, 0 deletions

diff --git a/spec/parcom_spec.cr b/spec/parcom_spec.cr
index dde6f21..feea102 100644
--- a/spec/parcom_spec.cr
+++ b/spec/parcom_spec.cr
@@ -721,3 +721,26 @@ describe SepBy do
   end
 end
 
+describe "Practical use" do
+  describe "Use case: text surrounded by whitespace" do
+    space = Satisfy(Char).new { |c| c.whitespace? }
+    non_space = Satisfy(Char).new { |c| !c.whitespace? }
+
+    # TODO: Figure out why mapping on this parser breaks
+    # initialization of `body`.
+    word_chars = Some.new(non_space)
+    ws = Some.new(space)
+
+    bookend = Optional.new(ws)
+    body = SepBy.new(word_chars, ws)
+    tokenizer = (bookend >> body << bookend).map do |arrs|
+      arrs.map { |chars| chars.join }
+    end
+
+    tokens = Tokens.from_string("test number 1 ")
+    result = tokenizer.parse(tokens)
+    result.value.should eq(["test", "number", "1"])
+    result.tokens.empty?.should be_true
+  end
+end
+