standard: Add tests for `Text.search_last`.

[nit.git] / lib / standard / string_search.nit

diff --git a/lib/standard/string_search.nit b/lib/standard/string_search.nit
index 0786ec9..091b3b2 100644 (file)
--- a/lib/standard/string_search.nit
+++ b/lib/standard/string_search.nit
@@ -84,6 +84,8 @@ interface Pattern
                res.add(new Match(s.to_s, i, s.length - i))
                return res
        end
+
+       protected fun is_in(s: Text): Bool do return search_index_in(s, 0) != -1
 end
 
 # BM_Pattern are pre-compiled string motif for the Boyer-Moore algorithm.
@@ -149,10 +151,10 @@ class BM_Pattern
        end
 
        # searched motif
-       var _motif: String
+       private var motif: String
 
        # length of the motif
-       var _length: Int
+       private var length: Int
 
        private fun bc(e: Char): Int
        do
@@ -164,10 +166,10 @@ class BM_Pattern
        end
 
        # good shifts
-       var _gs: Array[Int]
+       private var gs: Array[Int]
        
        # bad characters
-       var _bc_table: Map[Char, Int]
+       private var bc_table: Map[Char, Int]
 
        private fun compute_bc
        do
@@ -332,6 +334,37 @@ redef class Text
        #     assert "I say hello to the world!".search_from("hello",7)       == null
        fun search_from(p: Pattern, from: Int): nullable Match do return p.search_in(self, from)
 
+       # Search the last occurence of the text `t`.
+       #
+       #     assert "bob".search_last("b").from == 2
+       #     assert "bob".search_last("bo").from == 0
+       #     assert "bob".search_last("ob").from == 1
+       #     assert "bobob".search_last("ob").from == 3
+       #     assert "bobbob".search_last("bb").from == 2
+       #     assert "bobbob".search_last("bob").from == 3
+       #     assert "bob".search_last("z") == null
+       #     assert "".search_last("b") == null
+       fun search_last(t: Text): nullable Match do
+               return search_last_up_to(t, length)
+       end
+
+       # Search the last occurence of the text `t` before `up_to`.
+       #
+       #     assert "bobbob".search_last_up_to("b", 3).from == 2
+       #     assert "bobbob".search_last_up_to("b", 6).from == 5
+       #     assert "bobbob".search_last_up_to("b", 0) == null
+       fun search_last_up_to(t: Text, up_to: Int): nullable Match do
+               var i = up_to - t.length
+
+               while i >= 0 do
+                       if substring(i, t.length) == t then
+                               return new Match(self.to_s, i, t.length)
+                       end
+                       i -= 1
+               end
+               return null
+       end
+
        # Search all occurrences of p into self.
        #
        #     var a = new Array[Int]
@@ -375,16 +408,10 @@ redef class Text
                return self.split_with(p).join(string)
        end
 
-       # Escape the four characters `<`, `>`, `&`, and `"` with their html counterpart
+       # Does `self` contains at least one instance of `pattern`?
        #
-       #     assert "a&b->\"x\"".html_escape      ==  "a&amp;b-&gt;&quot;x&quot;"
-       fun html_escape: SELFTYPE
-       do
-               var ret = self
-               if ret.chars.has('&') then ret = ret.replace('&', "&amp;")
-               if ret.chars.has('<') then ret = ret.replace('<', "&lt;")
-               if ret.chars.has('>') then ret = ret.replace('>', "&gt;")
-               if ret.chars.has('"') then ret = ret.replace('"', "&quot;")
-               return ret
-       end
+       #     assert "hello".has('l')
+       #     assert "hello".has("ll")
+       #     assert not "hello".has("lll")
+       fun has(pattern: Pattern): Bool do return pattern.is_in(self)
 end