Simple string parser specs.

vic · Jan 21, 2011 · b044ca1 · b044ca1
1 parent cd22554
commit b044ca1
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Showing 5 changed files with 89 additions and 15 deletions.
diff --git a/lib/akin/parser/language.rb b/lib/akin/parser/language.rb
@@ -89,10 +89,10 @@ def fwd
       end
     end
 
-    module Number
+    module NumberLiteral
       def self./(base)
         Module.new do
-          include Number
+          include NumberLiteral
           define_method(:base) { base }
         end
       end
@@ -107,6 +107,12 @@ def text
       end
     end
 
+    module StringLiteral
+      def parts
+        self[1]
+      end
+    end
+
     module Language
       class << self
         attr_accessor :syntax

diff --git a/lib/akin/parser/match.rb b/lib/akin/parser/match.rb
@@ -21,7 +21,7 @@ def clone
 
     class Matcher
 
-      [ :name, :mixin, :block, :seq, :min, :max, :but, :true, :parse ].tap do |attrs|
+      [ :name, :mixin, :block, :seq, :min, :max, :pos, :true, :parse ].tap do |attrs|
         attr_reader *attrs
 
         define_method(:with) do |map|
@@ -43,15 +43,15 @@ class Matcher
 
       def initialize(block)
         @lookup = block
-        @true, @but, @min, @max = true, true, 1, 1
+        @true, @pos, @min, @max = true, true, 1, 1
       end
 
       def lookup(name)
         @lookup.call(name)
       end
 
       def but
-        with :but => !@but
+        with :pos => !@pos
       end
 
       def not
@@ -120,7 +120,7 @@ def |(other)
     private
 
       def positive?(bool)
-        if @but
+        if @pos
           bool
         else
           !bool
@@ -143,6 +143,7 @@ def match_new(positive, from, to, fwd, &block)
           m.to = to
           m.fwd = fwd
           m.tap(&block) if block
+          m.expected = self unless positive
         end
       end
 
@@ -178,7 +179,7 @@ def match_all(input, ary)
         match, at = nil, input
         ary.each_with_index do |item, index|
           match = match_single(at, item)
-          if match.positive?
+          if @true && match.positive?
             at = match.fwd
             all << match
             named[match.name] = match if match.name
@@ -189,12 +190,12 @@ def match_all(input, ary)
         end
         if all.size == 1
           match = all.first
-          match.extend @mixin if @mixin && match.positive? && @but == true
+          match.extend @mixin if @mixin && match.positive? && @pos
         else
           match = match_positive(input, all.last.to, all.last.fwd) do |match|
             match.ary = all
             match.map = named
-            match.extend @mixin if @mixin && @but == true
+            match.extend @mixin if @mixin && @pos
           end
         end
         match
@@ -261,7 +262,7 @@ def match_single(input, rule)
     class Match
       include Enumerable
 
-      attr_accessor :name, :from, :to, :fwd, :ary, :map, :positive
+      attr_accessor :name, :from, :to, :fwd, :ary, :map, :positive, :expected
 
       def text
         buff = ""

diff --git a/lib/akin/parser/syntax.rb b/lib/akin/parser/syntax.rb
@@ -5,10 +5,15 @@ module Parser
       a(:eof)             .is nil
       a(:any)             .is /./
 
+      a(:dollar)          .is "$"
       a(:dash)            .is "-"
       a(:slash)           .is "/"
       a(:underscore)      .is "_"
       a(:back_slash)      .is "\\"
+      a(:dot)             .is "."
+      a(:comma)           .is ","
+      a(:collon)          .is ":"
+      a(:semicollon)      .is ";"
 
       a(:unix_eol)        .is "\n"
       a(:win_eol)         .is "\r\n"
@@ -34,13 +39,27 @@ module Parser
         a(digit, a([ digit, a(:underscore, digit) ]).any)
       end
 
-      a(:bin_int).as(Number/2)  .is "0", /[bB]/, a(:digits).of(:oct_digit)
-      a(:oct_int).as(Number/8)  .is "0", a(/[oO]/).opt, a(:digits).of(:oct_digit)
-      a(:dec_int).as(Number/10) .is a(:digits).of(:dec_digit)
-      a(:hex_int).as(Number/16) .is "0", /[xX]/, a(:digits).of(:hex_digit)
+      a(:bin_int).as(NumberLiteral/2)  .is "0", /[bB]/, a(:digits).of(:oct_digit)
+      a(:oct_int).as(NumberLiteral/8)  .is "0", a(/[oO]/).opt, a(:digits).of(:oct_digit)
+      a(:dec_int).as(NumberLiteral/10) .is a(:digits).of(:dec_digit)
+      a(:hex_int).as(NumberLiteral/16) .is "0", /[xX]/, a(:digits).of(:hex_digit)
 
       a(:integer).is [:bin_int, :hex_int, :oct_int, :dec_int]
 
+      text = lambda do |left, right|
+        interpol = a(:dollar, :table)
+        escaped = a(:back_slash, [:dollar, right])
+        char = a(right.not, :any)
+        content = interpol | (escaped | char).many
+        a(left, content.any, right)
+      end
+
+      a(:string).as(StringLiteral).is text.call(a("\""), a("\""))
+      a(:mstring).as(StringLiteral).tap do |ms|
+        mq = a("\"", "\"", "\"")
+        ms.is text.call(mq, mq)
+      end
+
     end
   end
 end
diff --git a/spec/parser/match_spec.rb b/spec/parser/match_spec.rb
@@ -151,6 +151,14 @@ def input(text)
       m.to.should == nil
       m.fwd.should == i
     end
+
+    it "does not consume input on invalid sequence match" do
+      m = a("a", "b", "c").not.match i = input("foo")
+      m.positive?.should be_true
+      m.from.should == i
+      m.to.should == nil
+      m.fwd.should == i
+    end
   end
 
   describe "+ operator" do
@@ -331,5 +339,16 @@ def input(text)
     end
   end
 
+
+  describe "composite rule" do
+    it "matches an enclosed text between abc" do
+      x = a("a", "b", "c")
+      y = a(x, a(x.not, /./).any, x)
+      y.match(input("abcabc")).positive?.should be_true
+      y.match(input("abc   abc")).positive?.should be_true
+      y.match(input("abcdefabc")).positive?.should be_true
+    end
+  end
+
 end
 
diff --git a/spec/parser/syntax_spec.rb b/spec/parser/syntax_spec.rb
@@ -56,7 +56,7 @@ def parse(name, input)
         m.fwd.position.logical.pos.should == [1, 9, 9]
       end
 
-      it "leaves the physical fwd logical position intact" do
+      it "leaves the physical fwd position intact" do
         m = parse a(:tab), "\thola"
         m.fwd.position.physical.pos.should == [1, 2, 2]
       end
@@ -165,4 +165,33 @@ def parse(name, input)
     end
   end # hex integer
 
+
+  describe "string" do
+    it "matches a simple string literal" do
+      m = parse(:string, %q("hello"))
+      m.parts.count.should == 1
+      m.to.position.logical.pos.should == [1, 7, 7]
+    end
+
+    it "matches a string literal with escaped quotes" do
+      m = parse(:string, %q("hell\"o"))
+      m.parts.count.should == 1
+      m.to.position.logical.pos.should == [1, 9, 9]
+    end
+  end
+
+  describe "multi string" do
+    it "matches a simple string literal" do
+      m = parse(:mstring, %q("""hello"""))
+      m.parts.count.should == 1
+      m.to.position.logical.pos.should == [1, 11, 11]
+    end
+
+    it "matches a string literal with escaped quotes" do
+      m = parse(:mstring, %q("""hell\"""o"""))
+      m.parts.count.should == 1
+      m.to.position.logical.pos.should == [1, 15, 15]
+    end
+  end
+
 end