Implement DataTable.toTable(List<Map<String,Object>>). Closes cucumber#433.

Author: DFUK

core/src/main/java/cucumber/runtime/table/TableConverter.java

@@ -12,6 +12,7 @@
 import cucumber.runtime.xstream.ListOfComplexTypeReader;
 import cucumber.runtime.xstream.ListOfSingleValueWriter;
 import cucumber.runtime.xstream.LocalizedXStreams;
+import cucumber.runtime.xstream.MapWriter;
 import gherkin.formatter.model.Comment;
 import gherkin.formatter.model.DataTableRow;
 import gherkin.util.Mapper;
@@ -180,6 +181,8 @@ public DataTable toTable(List<?> objects, String... columnNames) {
                     // XStream needs an instance of ArrayList
                     object = new ArrayList<Object>(asList((Object[]) object));
                     writer = new ListOfSingleValueWriter();
+                } else if (object instanceof Map) {
+                    writer = new MapWriter(asList(columnNames));
                 } else {
                     writer = new ComplexTypeWriter(asList(columnNames));
                 }

core/src/main/java/cucumber/runtime/xstream/ComplexTypeWriter.java

@@ -20,13 +20,13 @@ public ComplexTypeWriter(List<String> columnNames) {
 
     @Override
     public List<String> getHeader() {
-        return columnNames.size() > 0 ? columnNames : fieldNames;
+        return columnNames.isEmpty() ? fieldNames : columnNames;
     }
 
     @Override
     public List<String> getValues() {
         CamelCaseStringConverter converter = new CamelCaseStringConverter();
-        if (columnNames.size() > 0) {
+        if (!columnNames.isEmpty()) {
             String[] explicitFieldValues = new String[columnNames.size()];
             int n = 0;
             for (String columnName : columnNames) {

core/src/main/java/cucumber/runtime/xstream/MapWriter.java

@@ -0,0 +1,67 @@
+package cucumber.runtime.xstream;
+
+import java.util.ArrayList;
+import java.util.LinkedHashMap;
+import java.util.List;
+import java.util.Map;
+
+/**
+ * Supports Map<String, Object> as the List item
+ */
+public class MapWriter extends CellWriter {
+    private final List<String> columnNames;
+    private final Map<String, Object> values = new LinkedHashMap<String, Object>();
+
+    private String key;
+
+    public MapWriter(List<String> columnNames) {
+        this.columnNames = columnNames;
+    }
+
+    @Override
+    public List<String> getHeader() {
+        return columnNames.isEmpty() ? new ArrayList<String>(values.keySet()) : columnNames;
+    }
+
+    @Override
+    public List<String> getValues() {
+        List<String> values = new ArrayList<String>(columnNames.size());
+        for (String columnName : getHeader()) {
+            Object value = this.values.get(columnName);
+            values.add(value == null ? "" : value.toString());
+        }
+        return values;
+    }
+
+    @Override
+    public void setValue(String value) {
+        if (key == null) {
+            key = value;
+        } else {
+            values.put(key, value);
+            key = null;
+        }
+    }
+
+    @Override
+    public void flush() {
+        throw new UnsupportedOperationException();
+    }
+
+    @Override
+    public void close() {
+        throw new UnsupportedOperationException();
+    }
+
+    @Override
+    public void startNode(String name) {
+    }
+
+    @Override
+    public void addAttribute(String name, String value) {
+    }
+
+    @Override
+    public void endNode() {
+    }
+}

core/src/test/java/cucumber/runtime/table/ToDataTableTest.java

@@ -9,8 +9,11 @@
 
 import java.lang.reflect.Type;
 import java.util.Date;
+import java.util.HashMap;
+import java.util.LinkedHashMap;
 import java.util.List;
 import java.util.Locale;
+import java.util.Map;
 
 import static java.util.Arrays.asList;
 import static org.junit.Assert.assertEquals;
@@ -127,20 +130,45 @@ public void converts_list_of_list_of_number_to_table() {
     }
 
     @Test
-    public void converts_list_of_array_of_string_to_table() {
+    public void converts_list_of_array_of_string_or_number_to_table_with_number_formatting() {
         List<Object[]> arrays = asList(
                 new Object[]{"name", "birthDate", "credits"},
-                new Object[]{"Sid Vicious", "10/05/1957", "1000"},
-                new Object[]{"Frank Zappa", "21/12/1940", "3000"}
+                new Object[]{"Sid Vicious", "10/05/1957", 1000},
+                new Object[]{"Frank Zappa", "21/12/1940", 3000}
         );
-        DataTable table = tc.toTable(arrays, "name", "credits", "birthDate");
+        DataTable table = tc.toTable(arrays);
         assertEquals("" +
                 "      | name        | birthDate  | credits |\n" +
-                "      | Sid Vicious | 10/05/1957 | 1000    |\n" +
-                "      | Frank Zappa | 21/12/1940 | 3000    |\n" +
+                "      | Sid Vicious | 10/05/1957 | 1,000   |\n" +
+                "      | Frank Zappa | 21/12/1940 | 3,000   |\n" +
                 "", table.toString());
     }
 
+    @Test
+    public void convert_list_of_maps_to_table() {
+        Map<String, Object> vicious = new LinkedHashMap<String, Object>();
+        vicious.put("name", "Sid Vicious");
+        vicious.put("birthDate", "10/05/1957");
+        vicious.put("credits", 1000);
+        Map<String, Object> zappa = new LinkedHashMap<String, Object>();
+        zappa.put("name", "Frank Zappa");
+        zappa.put("birthDate", "21/12/1940");
+        zappa.put("credits", 3000);
+        List<Map<String, Object>> maps = asList(vicious, zappa);
+
+        assertEquals("" +
+                "      | name        | credits | birthDate  |\n" +
+                "      | Sid Vicious | 1,000   | 10/05/1957 |\n" +
+                "      | Frank Zappa | 3,000   | 21/12/1940 |\n" +
+                "", tc.toTable(maps, "name", "credits", "birthDate").toString());
+
+        assertEquals("" +
+                "      | name        | birthDate  | credits |\n" +
+                "      | Sid Vicious | 10/05/1957 | 1,000   |\n" +
+                "      | Frank Zappa | 21/12/1940 | 3,000   |\n" +
+                "", tc.toTable(maps).toString());
+    }
+
     // No setters
     public static class UserPojo {
         public Integer credits;