Fix SolderBridge check to only check across multiple

We should not generate an error when overlapping a single copper element
with a soldermask that is not associated with copper.

Fixes https://gitlab.com/kicad/code/kicad/issues/10906

pcbnew/drc/drc_test_provider_solder_mask.cpp

@@ -333,11 +333,17 @@ void DRC_TEST_PROVIDER_SOLDER_MASK::testItemAgainstItems( BOARD_ITEM* aItem,
                 if( otherNet > 0 && otherNet == itemNet )
                     return false;
 
+                if( aItem->GetParentFootprint() && other->GetParentFootprint() )
+                {
+                    int attr = static_cast<FOOTPRINT*>( aItem->GetParentFootprint() )->GetAttributes();
+
+                    if( attr & FP_ALLOW_SOLDERMASK_BRIDGES )
+                        return false;
+                }
+
                 if( pad && otherPad && pad->GetParent() == otherPad->GetParent() )
                 {
-                    if( pad->GetParent()->GetAttributes() & FP_ALLOW_SOLDERMASK_BRIDGES )
+                    if( pad->SameLogicalPadAs( otherPad ) )
-                        return false;
-                    else if( pad->SameLogicalPadAs( otherPad ) )
                         return false;
                 }
 
@@ -401,8 +407,13 @@ void DRC_TEST_PROVIDER_SOLDER_MASK::testItemAgainstItems( BOARD_ITEM* aItem,
                     {
                         std::pair<BOARD_ITEM*, PCB_LAYER_ID> key = { aItem, aRefLayer };
 
+                        // If the mask collides with the first object, add the object
+                        // net to our map and stop.  This cannot be an error yet.
                         if( m_maskApertureNetMap.count( key ) == 0 )
+                        {
                             m_maskApertureNetMap[ key ] = otherNet;
+                            return true;
+                        }
 
                         if( m_maskApertureNetMap.at( key ) == otherNet && otherNet > 0 )
                             return true;
@@ -413,7 +424,10 @@ void DRC_TEST_PROVIDER_SOLDER_MASK::testItemAgainstItems( BOARD_ITEM* aItem,
                         std::pair<BOARD_ITEM*, PCB_LAYER_ID> key = { other, aRefLayer };
 
                         if( m_maskApertureNetMap.count( key ) == 0 )
+                        {
                             m_maskApertureNetMap[ key ] = itemNet;
+                            return true;
+                        }
 
                         if( m_maskApertureNetMap.at( key ) == itemNet && itemNet > 0 )
                             return true;

qa/data/issue10906.kicad_pcb

@@ -0,0 +1,103 @@
+(kicad_pcb (version 20220211) (generator pcbnew)
+
+  (general
+    (thickness 1.6)
+  )
+
+  (paper "A4")
+  (layers
+    (0 "F.Cu" signal)
+    (31 "B.Cu" signal)
+    (32 "B.Adhes" user "B.Adhesive")
+    (33 "F.Adhes" user "F.Adhesive")
+    (34 "B.Paste" user)
+    (35 "F.Paste" user)
+    (36 "B.SilkS" user "B.Silkscreen")
+    (37 "F.SilkS" user "F.Silkscreen")
+    (38 "B.Mask" user)
+    (39 "F.Mask" user)
+    (40 "Dwgs.User" user "User.Drawings")
+    (41 "Cmts.User" user "User.Comments")
+    (42 "Eco1.User" user "User.Eco1")
+    (43 "Eco2.User" user "User.Eco2")
+    (44 "Edge.Cuts" user)
+    (45 "Margin" user)
+    (46 "B.CrtYd" user "B.Courtyard")
+    (47 "F.CrtYd" user "F.Courtyard")
+    (48 "B.Fab" user)
+    (49 "F.Fab" user)
+    (50 "User.1" user)
+    (51 "User.2" user)
+    (52 "User.3" user)
+    (53 "User.4" user)
+    (54 "User.5" user)
+    (55 "User.6" user)
+    (56 "User.7" user)
+    (57 "User.8" user)
+    (58 "User.9" user)
+  )
+
+  (setup
+    (pad_to_mask_clearance 0)
+    (pcbplotparams
+      (layerselection 0x00010fc_ffffffff)
+      (disableapertmacros false)
+      (usegerberextensions false)
+      (usegerberattributes true)
+      (usegerberadvancedattributes true)
+      (creategerberjobfile true)
+      (dashed_line_dash_ratio 12.000000)
+      (dashed_line_gap_ratio 3.000000)
+      (svgprecision 4)
+      (excludeedgelayer true)
+      (plotframeref false)
+      (viasonmask false)
+      (mode 1)
+      (useauxorigin false)
+      (hpglpennumber 1)
+      (hpglpenspeed 20)
+      (hpglpendiameter 15.000000)
+      (dxfpolygonmode true)
+      (dxfimperialunits true)
+      (dxfusepcbnewfont true)
+      (psnegative false)
+      (psa4output false)
+      (plotreference true)
+      (plotvalue true)
+      (plotinvisibletext false)
+      (sketchpadsonfab false)
+      (subtractmaskfromsilk false)
+      (outputformat 1)
+      (mirror false)
+      (drillshape 1)
+      (scaleselection 1)
+      (outputdirectory "")
+    )
+  )
+
+  (net 0 "")
+
+  (footprint "Connector_Wire:SolderWirePad_1x01_SMD_1x2mm" (layer "F.Cu")
+    (tedit 620FF1C8) (tstamp 2e642b3e-a476-4c54-9a52-dcea955640cd)
+    (at 136.84 58.35)
+    (descr "Wire Pad, Square, SMD Pad,  5mm x 10mm,")
+    (tags "MesurementPoint Square SMDPad 5mmx10mm ")
+    (attr exclude_from_pos_files exclude_from_bom)
+    (fp_text reference "REF**" (at 0 -2.54) (layer "F.SilkS") hide
+        (effects (font (size 1 1) (thickness 0.15)))
+      (tstamp b1086f75-01ba-4188-8d36-75a9e2828ca9)
+    )
+    (fp_text value "" (at 0 2.54) (layer "F.Fab") hide
+        (effects (font (size 1 1) (thickness 0.15)))
+      (tstamp 716e31c5-485f-40b5-88e3-a75900da9811)
+    )
+    (fp_rect (start -0.762 -0.508) (end 1.016 0.762)
+      (stroke (width 0) (type solid)) (fill solid) (layer "F.Cu") (tstamp e87a6f80-914f-4f62-9c9f-9ba62a88ee3d))
+    (fp_rect (start -0.762 -0.508) (end 1.016 0.762)
+      (stroke (width 0) (type solid)) (fill solid) (layer "F.Mask") (tstamp df3dc9a2-ba40-4c3a-87fe-61cc8e23d71b))
+  )
+
+  (gr_rect (start 135.25 57.21) (end 138.55 60.51)
+    (stroke (width 0.05) (type default)) (fill none) (layer "Edge.Cuts") (tstamp 2f0570b6-86da-47a8-9e56-ce60c431c534))
+
+)

qa/data/solder_mask_bridge_test.kicad_pro

@@ -56,7 +56,8 @@
         }
       ],
       "drc_exclusions": [
-        "lib_footprint_issues|154305000|81417500|3bd3a1e0-b35d-4974-99fa-33d3eee5d601|00000000-0000-0000-0000-000000000000"
+        "lib_footprint_issues|154305000|81417500|3bd3a1e0-b35d-4974-99fa-33d3eee5d601|00000000-0000-0000-0000-000000000000",
+        "lib_footprint_mismatch|194730000|83947750|970e0f64-111f-41e3-9f5a-fb0d0f6fa101|00000000-0000-0000-0000-000000000000"
       ],
       "meta": {
         "version": 2
@@ -80,6 +81,7 @@
         "items_not_allowed": "error",
         "length_out_of_range": "error",
         "lib_footprint_issues": "ignore",
+        "lib_footprint_mismatch": "error",
         "malformed_courtyard": "error",
         "microvia_drill_out_of_range": "error",
         "missing_courtyard": "ignore",
@@ -129,6 +131,46 @@
         "solder_mask_to_copper_clearance": 0.0,
         "use_height_for_length_calcs": true
       },
+      "teardrop_options": [
+        {
+          "td_allow_use_two_tracks": true,
+          "td_curve_segcount": 5,
+          "td_on_pad_in_zone": false,
+          "td_onpadsmd": true,
+          "td_onroundshapesonly": false,
+          "td_ontrackend": false,
+          "td_onviapad": true
+        }
+      ],
+      "teardrop_parameters": [
+        {
+          "td_curve_segcount": 0,
+          "td_height_ratio": 1.0,
+          "td_length_ratio": 0.5,
+          "td_maxheight": 2.0,
+          "td_maxlen": 1.0,
+          "td_target_name": "td_round_shape",
+          "td_width_to_size_filter_ratio": 0.9
+        },
+        {
+          "td_curve_segcount": 0,
+          "td_height_ratio": 1.0,
+          "td_length_ratio": 0.5,
+          "td_maxheight": 2.0,
+          "td_maxlen": 1.0,
+          "td_target_name": "td_rect_shape",
+          "td_width_to_size_filter_ratio": 0.9
+        },
+        {
+          "td_curve_segcount": 0,
+          "td_height_ratio": 1.0,
+          "td_length_ratio": 0.5,
+          "td_maxheight": 2.0,
+          "td_maxlen": 1.0,
+          "td_target_name": "td_track_end",
+          "td_width_to_size_filter_ratio": 0.9
+        }
+      ],
       "track_widths": [
         0.0,
         0.2,

qa/pcbnew/drc/test_drc_regressions.cpp

@@ -57,7 +57,8 @@ BOOST_FIXTURE_TEST_CASE( DRCFalsePositiveRegressions, DRC_REGRESSION_TEST_FIXTUR
                                                     // selective inner copper layers
                                     "issue7567",    // DRC constraint to disallow holes gets SMD pads also
                                     "issue7975",    // Differential pair gap out of range fault by DRC
-                                    "issue8407"     // PCBNEW: Arc for diff pair has clearance DRC error
+                                    "issue8407",    // PCBNEW: Arc for diff pair has clearance DRC error
+                                    "issue10906"    // Soldermask bridge for only one object
                                   };
 
     for( const wxString& relPath : tests )

qa/pcbnew/drc/test_solder_mask_bridging.cpp

@@ -66,14 +66,14 @@ BOOST_FIXTURE_TEST_CASE( DRCSolderMaskBridgingTest, DRC_REGRESSION_TEST_FIXTURE
 
     bds.m_DRCEngine->RunTests( EDA_UNITS::MILLIMETRES, true, false );
 
-    if( violations.size() == 4 )
+    if( violations.size() == 5 )
     {
         BOOST_CHECK_EQUAL( 1, 1 );  // quiet "did not check any assertions" warning
         BOOST_TEST_MESSAGE( "DRC solder mask bridge test passed" );
     }
     else
     {
-        BOOST_CHECK_EQUAL( violations.size(), 4 );
+        BOOST_CHECK_EQUAL( violations.size(), 5 );
 
         std::map<KIID, EDA_ITEM*> itemMap;
         m_board->FillItemMap( itemMap );