Make limit work.

Extra functions on JS/Jackson object.

distribution/lib/Standard/Base/0.0.0-dev/src/Data/Java_Json.enso

@@ -2,6 +2,7 @@ import project.Any.Any
 import project.Data.Array_Proxy.Array_Proxy
 import project.Data.Json.Invalid_JSON
 import project.Data.Json.JS_Object
+import project.Data.Numbers.Integer
 import project.Data.Numbers.Number
 import project.Data.Text.Text
 import project.Data.Vector.Vector
@@ -13,6 +14,7 @@ import project.Nothing.Nothing
 import project.Panic.Panic
 from project.Data.Boolean import Boolean, False, True
 from project.Data.Json.Extensions import all
+from project.Data.Ordering import all
 from project.Data.Text.Extensions import all
 from project.Metadata.Choice import Option
 from project.Metadata.Widget import Single_Choice
@@ -104,6 +106,14 @@ type Jackson_Object
     field_names : Vector
     field_names self = self.field_array
 
+    ## GROUP Conversions
+       Maps ths object to a Vector of Pairs.
+    map : (Text->Any->Any) -> Vector
+    map self action=[_,_] =
+        self.field_names.map key->
+            value = self.get key
+            action key value
+
     ## GROUP Metadata
        Gets the number of keys in the object.
     length : Number
@@ -141,3 +151,26 @@ make_field_name_selector js_object display=Display.Always =
 ## Extension for Text to allow use.
 Text.parse_fast_json : Nothing | Boolean | Number | Text | Vector | Jackson_Object
 Text.parse_fast_json self = Java_Json.parse self
+
+## PRIVATE
+type Jackson_Object_Comparator
+    ## PRIVATE
+    compare : Jackson_Object -> Jackson_Object -> (Ordering|Nothing)
+    compare obj1 obj2 =
+        obj1_keys = obj1.field_names
+        obj2_keys = obj2.field_names
+        same_values = obj1_keys.length == obj2_keys.length && obj1_keys.all key->
+            (obj1.get key == obj2.at key).catch No_Such_Key _->False
+        if same_values then Ordering.Equal else Nothing
+
+    ## PRIVATE
+    hash : Jackson_Object -> Integer
+    hash obj =
+        values_hashes = obj.field_names.map field_name->
+            val = obj.get field_name
+            Comparable.from val . hash val
+        # Return sum, as we don't care about ordering of field names
+        values_hashes.fold 0 (+)
+
+## PRIVATE
+Comparable.from (_:Jackson_Object) = Jackson_Object_Comparator

distribution/lib/Standard/Base/0.0.0-dev/src/Data/Json.enso

@@ -168,6 +168,14 @@ type JS_Object
     field_names self =
         Vector.from_polyglot_array (get_property_names self.js_object)
 
+    ## GROUP Conversions
+       Maps ths object to a Vector of Pairs.
+    map : (Text->Any->Any) -> Vector
+    map self action=[_,_] =
+        self.field_names.map key->
+            value = self.get key
+            action key value
+
     ## GROUP Metadata
        Gets the number of keys in the object.
     length : Number

distribution/lib/Standard/Base/0.0.0-dev/src/System/File_By_Line.enso

@@ -46,7 +46,8 @@ type File_By_Line
        - limit_lines: The number of lines to read (defaults to all lines).
        - filter_func: The filter to apply to each line (defaults to no filter).
        - row_map: The row map to use (defaults to a new row map).
-    Reader file:File encoding:Encoding limit_lines:(Integer|Nothing) filter_func row_map
+       - file_end: The end of the file in bytes.
+    Reader file:File encoding:Encoding limit_lines:(Integer|Nothing) filter_func row_map file_end=file.size
 
     ## Reads a specific line from the file.
 
@@ -77,7 +78,7 @@ type File_By_Line
     to_vector : Vector Text
     to_vector self = File_Error.handle_java_exceptions self.file <|
         end_at = if self.limit_lines.is_nothing then Nothing else self.limit_lines-1
-        FileLineReader.readLines self.java_file self.row_map 0 end_at self.charset self.filter_func
+        FileLineReader.readLines self.java_file self.file_end self.row_map 0 end_at self.charset self.filter_func
 
     ## Performs an action on each line.
 
@@ -126,23 +127,25 @@ type File_By_Line
     skip : Integer -> File_By_Line
     skip self lines:Integer =
         ## Read the line
-        position = if self.row_map.getSize > lines then self.row_map.get lines else
-            for_each_lines self 0 lines Nothing
-            self.row_map.get self.row_map.getSize-1
-        row_map = LongArrayList.new
-        row_map.add position
-        self.log "Created Skipped Parent"
+        create_row_map parent line =
+            position = if parent.row_map.getSize > line then parent.row_map.get line else
+                for_each_lines self 0 line Nothing
+                parent.row_map.get parent.row_map.getSize-1
+            row_map = LongArrayList.new
+            row_map.add position
+            parent.log "Created Skipped Row Map ("+line.to_text+")"
+            row_map
 
         new_limit = if self.limit_lines.is_nothing then lines else lines.min self.limit_lines
-        File_By_Line.Reader self.file self.encoding new_limit self.filter_func row_map
+        File_By_Line.Reader self.file self.encoding new_limit self.filter_func (create_row_map self lines) self.file_end
 
     ## Limits a file to a specific number of lines.
 
        Arguments
        - lines: The number of lines to limit the file to.
     limit : Integer -> File_By_Line
     limit self lines:Integer =
-        File_By_Line.Reader self.file self.encoding lines self.filter_func self.row_map
+        File_By_Line.Reader self.file self.encoding lines self.filter_func self.row_map self.file_end
 
     ## Filters the file by a predicate.
 
@@ -156,17 +159,28 @@ type File_By_Line
             _ -> FileLineReader.wrapBooleanFilter predicate self.charset
 
         ## Find the index of the first line matching the new index.
-        end_at = if self.limit_lines.is_nothing then -1 else self.limit_lines-1
-        first_index = FileLineReader.findFirstNewFilter self.java_file self.row_map end_at self.charset self.filter_func new_filter
-        new_row_map = LongArrayList.new
-        new_row_map.add first_index
+        make_filter_map parent new_filter =
+            end_at = if parent.limit_lines.is_nothing then -1 else parent.limit_lines-1
+            first_index = FileLineReader.findFirstNewFilter parent.java_file parent.file_end parent.row_map end_at parent.charset parent.filter_func new_filter
+            new_row_map = LongArrayList.new
+            new_row_map.add first_index
+            parent.log "Found Filter Start - "+first_index.to_text
+            new_row_map
 
         ## Merge the two predicates together.
         new_predicate = if self.filter_func.is_nothing then new_filter else
             FileLineReader.mergeTwoFilters self.filter_func new_filter
 
-        ## Need to ensure the parent limit is obeyed - for now we just use it but should be applied on level above
-        File_By_Line.Reader self.file self.encoding self.limit_lines new_predicate new_row_map
+        ## If the parent is limited need to limit the child by end position in file.
+        if self.limit_lines == Nothing then File_By_Line.Reader self.file self.encoding Nothing new_predicate (make_filter_map self new_filter) self.file_end else
+            ## Find the index of the last line matching the new index.
+            index_of parent line =
+                file_len = if parent.row_map.getSize > line then parent.row_map.get line else
+                    for_each_lines self 0 line Nothing
+                    parent.row_map.get parent.row_map.getSize-1
+                parent.log "Created File End ("+line.to_text+") - "+file_len.to_text
+                file_len
+            File_By_Line.Reader self.file self.encoding Nothing new_predicate (make_filter_map self new_filter) (index_of self self.limit_lines)
 
     ## ADVANCED
        Exports the row_map
@@ -188,19 +202,20 @@ type File_By_Line
    Reads a specific line from the file.
 read_line : File_By_Line->Integer->Any->Any
 read_line file:File_By_Line line:Integer=0 ~default=Nothing = File_Error.handle_java_exceptions file.file <|
-    FileLineReader.readSingleLine file.java_file file.row_map line file.charset file.filter_func . if_nothing default
+    FileLineReader.readSingleLine file.java_file file.file_end file.row_map line file.charset file.filter_func . if_nothing default
 
 ## PRIVATE
    Performs an action on each line in the file.
 for_each_lines : File_By_Line->Integer->(Integer|Nothing)->Any->Any
 for_each_lines file:File_By_Line start_at:Integer end_at:(Integer|Nothing) action = File_Error.handle_java_exceptions file.file <|
     java_file = file.java_file
     row_map = file.row_map
+    file_end = file.file_end
     charset = file.charset
 
     ## First if we haven't read the found the start_at line we need to find that.
-    if start_at >= row_map.getSize then FileLineReader.readSingleLine java_file row_map start_at charset file.filter_func
+    if start_at >= row_map.getSize then FileLineReader.readSingleLine java_file file_end row_map start_at charset file.filter_func
 
     ## Now we can read the lines we need.
-    if row_map.getOrLast start_at >= java_file.length then Error.throw (Index_Out_Of_Bounds.Error start_at row_map.getSize) else
-        FileLineReader.forEachLine java_file row_map start_at (end_at.if_nothing -1) charset file.filter_func action
+    if row_map.getOrLast start_at >= file_end then Error.throw (Index_Out_Of_Bounds.Error start_at row_map.getSize) else
+        FileLineReader.forEachLine java_file file_end row_map start_at (end_at.if_nothing -1) charset file.filter_func action

std-bits/base/src/main/java/org/enso/base/FileLineReader.java

@@ -111,13 +111,12 @@ private static boolean scanLine(MappedByteBuffer buffer) {
   }
 
   // ** Reads a line from a file at the given index using the existing rowMap. */
-  private static String readLineByIndex(File file, LongArrayList rowMap, int index, Charset charset)
+  private static String readLineByIndex(File file, long length, LongArrayList rowMap, int index, Charset charset)
       throws IOException {
     if (index >= rowMap.getSize()) {
       throw new IndexOutOfBoundsException(index);
     }
 
-    long length = file.length();
     long position = rowMap.get(index);
     if (position >= length) {
       return null;
@@ -150,30 +149,32 @@ private static String readLineByIndex(File file, LongArrayList rowMap, int index
   // ** Scans forward in a file and returns the line at the given index. */
   public static String readSingleLine(
       File file,
+      long length,
       LongArrayList rowMap,
       int index,
       Charset charset,
       Function<ByteArrayOutputStreamWithContains, String> filter)
       throws IOException {
     int size = rowMap.getSize();
     if (index != -1 && size > index) {
-      return readLineByIndex(file, rowMap, index, charset);
+      return readLineByIndex(file, length, rowMap, index, charset);
     }
 
     // Start at the last known line and scan forward.
-    return forEachLine(file, rowMap, size - 1, index, charset, filter, null);
+    return forEachLine(file, length, rowMap, size - 1, index, charset, filter, null);
   }
 
   public static List<String> readLines(
       File file,
+      long length,
       LongArrayList rowMap,
       int startAt,
       int endAt,
       Charset charset,
       Function<ByteArrayOutputStreamWithContains, String> filter)
       throws IOException {
     List<String> result = new ArrayList<>();
-    forEachLine(file, rowMap, startAt, endAt, charset, filter, (index, line) -> result.add(line));
+    forEachLine(file, length, rowMap, startAt, endAt, charset, filter, (index, line) -> result.add(line));
     return result;
   }
 
@@ -189,6 +190,7 @@ public static List<String> readLines(
   // * *//
   public static String forEachLine(
       File file,
+      long length,
       LongArrayList rowMap,
       int startAt,
       int endAt,
@@ -197,11 +199,12 @@ public static String forEachLine(
       BiConsumer<Integer, String> action)
       throws IOException {
     return innerForEachLine(
-        file, rowMap, startAt, endAt, charset, filter, action, new CancellationToken());
+        file, length, rowMap, startAt, endAt, charset, filter, action, new CancellationToken());
   }
 
   private static String innerForEachLine(
       File file,
+      long length,
       LongArrayList rowMap,
       int startAt,
       int endAt,
@@ -215,7 +218,6 @@ private static String innerForEachLine(
     }
     int index = action == null ? rowMap.getSize() - 1 : startAt;
 
-    long length = file.length();
     long position = rowMap.get(index);
     if (position >= length) {
       return null;
@@ -299,6 +301,7 @@ private static String innerForEachLine(
   // filter. */
   public static long findFirstNewFilter(
       File file,
+      long length,
       LongArrayList rowMap,
       int endAt,
       Charset charset,
@@ -316,7 +319,7 @@ public static long findFirstNewFilter(
             token.cancel();
           }
         };
-    innerForEachLine(file, rowMap, 0, endAt, charset, filter, action, token);
+    innerForEachLine(file, length, rowMap, 0, endAt, charset, filter, action, token);
     return result.isEmpty() ? rowMap.get(rowMap.getSize() - 1) : result.get(0);
   }