[processing][saga] Remove duplicate polygon self intersection alg, fix params and add test

Author: nyalldawson

python/plugins/processing/algs/saga/description/PolygonSelf-Intersection.txt

@@ -1,5 +1,5 @@
 Polygon Self-Intersection
 shapes_polygons
-QgsProcessingParameterFeatureSource|POLYGONS|Polygons|-1|None|False
-QgsProcessingParameterFeatureSource|ID|Identifier|5|None|False
-QgsProcessingParameterVectorDestination|INTERSECT|Intersection
+QgsProcessingParameterFeatureSource|POLYGONS|Polygons|2|None|False
+QgsProcessingParameterField|ID|Identifier|None|POLYGONS|-1|False|True
+QgsProcessingParameterVectorDestination|INTERSECT|Intersection

python/plugins/processing/algs/saga/description/PolygonSelfIntersection.txt

@@ -0,0 +1,27 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<SAGA_METADATA>
+  <HISTORY saga-version="2.3.1">
+    <MODULE library="shapes_polygons" id="12" name="Polygon Self-Intersection">
+      <OPTION type="table_field" id="ID" name="Identifier" index="-1">&lt;not set&gt;</OPTION>
+      <INPUT type="shapes" id="POLYGONS" name="Polygons">
+        <FILE>/tmp/processing_8acf43932cd84783ae0090b3989dbd5b/703e941d2820467086c0ad7c06adc266/POLYGONS.shp</FILE>
+      </INPUT>
+      <OUTPUT type="shapes" id="INTERSECT" name="Intersection">POLYGONS [self-intersection]</OUTPUT>
+    </MODULE>
+  </HISTORY>
+  <SOURCE>
+    <FILE></FILE>
+    <DATABASE>
+      <FIELDS>
+        <FIELD TYPE="STRING">id_b</FIELD>
+        <FIELD TYPE="STRING">ID</FIELD>
+      </FIELDS>
+    </DATABASE>
+    <PROJECTION>
+      <OGC_WKT>PROJCS["WGS_1984_Web_Mercator_Auxiliary_Sphere",GEOGCS["GCS_WGS_1984",DATUM["D_WGS_1984",SPHEROID["WGS_1984",6378137.0,298.257223563]],PRIMEM["Greenwich",0.0],UNIT["Degree",0.0174532925199433]],PROJECTION["Mercator_Auxiliary_Sphere"],PARAMETER["False_Easting",0.0],PARAMETER["False_Northing",0.0],PARAMETER["Central_Meridian",0.0],PARAMETER["Standard_Parallel_1",0.0],PARAMETER["Auxiliary_Sphere_Type",0.0],UNIT["Meter",1.0]]</OGC_WKT>
+      <PROJ4></PROJ4>
+      <EPSG>-1</EPSG>
+    </PROJECTION>
+  </SOURCE>
+  <DESCRIPTION></DESCRIPTION>
+</SAGA_METADATA>

python/plugins/processing/tests/testdata/expected/saga/polygon_self_intersection.dbf

@@ -0,0 +1 @@
+PROJCS["WGS 84 / Pseudo-Mercator",GEOGCS["WGS 84",DATUM["WGS_1984",SPHEROID["WGS 84",6378137,298.257223563,AUTHORITY["EPSG","7030"]],AUTHORITY["EPSG","6326"]],PRIMEM["Greenwich",0,AUTHORITY["EPSG","8901"]],UNIT["degree",0.0174532925199433,AUTHORITY["EPSG","9122"]],AUTHORITY["EPSG","4326"]],PROJECTION["Mercator_1SP"],PARAMETER["central_meridian",0],PARAMETER["scale_factor",1],PARAMETER["false_easting",0],PARAMETER["false_northing",0],UNIT["metre",1,AUTHORITY["EPSG","9001"]],AXIS["X",EAST],AXIS["Y",NORTH],EXTENSION["PROJ4","+proj=merc +a=6378137 +b=6378137 +lat_ts=0.0 +lon_0=0.0 +x_0=0.0 +y_0=0 +k=1.0 +units=m +nadgrids=@null +wktext +no_defs"],AUTHORITY["EPSG","3857"]]

python/plugins/processing/tests/testdata/expected/saga/polygon_self_intersection.mshp

@@ -346,3 +346,15 @@ tests:
         name: expected/saga/polygon_intersect.shp
         type: vector
 
+
+  - algorithm: saga:polygonselfintersection
+    name: Polygon self intersection
+    params:
+      POLYGONS:
+        name: custom/overlay2_b.geojson
+        type: vector
+    results:
+      INTERSECT:
+        name: expected/saga/polygon_self_intersection.shp
+        type: vector
+