trim newline

elua.moon

@@ -38,13 +38,24 @@ class Parser
         @pos += 1
 
     close_start, close_stop = @str\find @close_tag, @pos, true
+    error "failed to find closing tag" unless close_start
+
     while @in_string @pos, close_start
       close_start, close_stop = @str\find @close_tag, close_stop, true
 
+    trim_newline = if "-" == @str\sub close_start - 1, close_start - 1
+      close_start -= 1
+      true
+
     kind = modifier == "=" and "interplate" or "code"
     @push_code kind, @pos, close_start - 1
 
     @pos = close_stop + 1
+
+    if trim_newline
+      if match = @str\match "^\n", @pos
+        @pos += #match
+
     true
 
   -- see if stop leaves us in the middle of a string
@@ -140,7 +151,7 @@ class Parser
 
           -- validate syntax
           unless loadstring assign
-            error "failed to parse: #{chunk[2]}"
+            error "failed to parse as expression: #{chunk[2]}"
 
           push "_b_i = _b_i + 1"
           push assign

spec/elua_spec.moon

@@ -76,12 +76,28 @@ This is my message to <%= [=[oh yeah  %>"]=] %>]]
           visitor: "yeah"
         }
       }
+
+
+      {
+        "hello"
+        "<%= 'hello' -%>
+"
+      }
+
     }
 
     for case in *cases
       it "should run template", ->
         assert.same case[1], render unpack case, 2
 
+    it "should error on unclosed tag", ->
+      assert.has_error ->
+        render "hello <%= world"
+
+    it "should fail on bad template", ->
+      assert.has_error ->
+        render "hello <%= if hello then print(nil) end%>"
+
   describe "Parser.in_string", ->
     cases = {
       { "hello world", false }