Int parsing + some tweaks

1 files changed, 41 insertions, 4 deletions

diff --git a/spec/practical/json_spec.cr b/spec/practical/json_spec.cr
index 7373d91..ed0fcfb 100644
--- a/spec/practical/json_spec.cr
+++ b/spec/practical/json_spec.cr
@@ -2,6 +2,8 @@ require "../spec_helper"
 
 include Parcom
 
+# NOTE: WORK IN PROGRESS
+
 alias JSONType = Nil \
                | Bool \
                | Int64 \
@@ -10,7 +12,7 @@ alias JSONType = Nil \
                | Array(JSONValue) \
                | Hash(String, JSONValue)
 
-class JSONValue
+struct JSONValue
   property data : JSONType
 
   def initialize(@data)
@@ -22,15 +24,25 @@ def json_null
 end
 
 def json_bool
-  t = Parser.token_sequence("true".chars).map { |_| JSONValue.new(true) }
-  f = Parser.token_sequence("false".chars).map { |_| JSONValue.new(false) }
-  t | f
+  t = Parser.token_sequence("true".chars).map { |_| true }
+  f = Parser.token_sequence("false".chars).map { |_| false }
+  (t | f).map { |b| JSONValue.new(b) }
+end
+
+# Only standard decimal ints for now
+def json_number
+  base_num = Parser(Char, Char).satisfy(&.ascii_number?).some.map do |cs|
+    cs.join.to_i64
+  end
+  sign = Parser.token('-').map { |_| -1 }.recover(1)
+  (sign + base_num).map { |s, n| JSONValue.new(s.to_i64 * n) }
 end
  
 def json_value : Parser(Char, JSONValue)
   Parser.first_of([
     json_null,
     json_bool,
+    json_number,
   ])
 end
 
@@ -59,6 +71,21 @@ describe "example: JSON parsing" do
     end
   end
 
+  describe "json_number" do
+    it "parses strings of digits and other key characters and converts to number" do
+      result = json_number.parse(Tokens.from_string("42"))
+      result.value.data.should eq(42)
+      result.tokens.empty?.should be_true
+
+      result = json_number.parse(Tokens.from_string("-42"))
+      result.value.data.should eq(-42)
+      result.tokens.empty?.should be_true
+
+      expect_raises(ParserFail) { json_number.parse(Tokens.from_string("")) }
+      expect_raises(ParserFail) { json_number.parse(Tokens.from_string("foo")) }
+    end
+  end
+
   describe "json_value" do
     it "parses null" do
       result = json_value.parse(Tokens.from_string("null"))
@@ -75,6 +102,16 @@ describe "example: JSON parsing" do
       result.value.data.should be_false
       result.tokens.empty?.should be_true
     end
+
+    it "parsers ints" do
+      result = json_value.parse(Tokens.from_string("42"))
+      result.value.data.should eq(42)
+      result.tokens.empty?.should be_true
+
+      result = json_value.parse(Tokens.from_string("-42"))
+      result.value.data.should eq(-42)
+      result.tokens.empty?.should be_true
+    end
   end
 end