add AnyInteresting function to Tags object

osmgeojson/convert.go

@@ -9,18 +9,6 @@ import (
 	"github.com/paulmach/osm/internal/mputil"
 )
 
-var uninterestingTags = map[string]bool{
-	"source":            true,
-	"source_ref":        true,
-	"source:ref":        true,
-	"history":           true,
-	"attribution":       true,
-	"created_by":        true,
-	"tiger:county":      true,
-	"tiger:tlid":        true,
-	"tiger:upload_uuid": true,
-}
-
 type context struct {
 	noID                   bool
 	noMeta                 bool
@@ -405,7 +393,7 @@ func hasInterestingTags(tags osm.Tags, ignore map[string]string) bool {
 
 	for _, tag := range tags {
 		k, v := tag.Key, tag.Value
-		if !uninterestingTags[k] &&
+		if !osm.UninterestingTags[k] &&
 			(ignore == nil || !(ignore[k] == "true" || ignore[k] == v)) {
 			return true
 		}

tag.go

@@ -7,6 +7,22 @@ import (
 	"sync"
 )
 
+// UninterestingTags are boring tags. If an element only has
+// these tags it does not usually need to be displayed.
+// For example, if a node with just these tags is part of a way, it
+// probably does not need its own icon along the way.
+var UninterestingTags = map[string]bool{
+	"source":            true,
+	"source_ref":        true,
+	"source:ref":        true,
+	"history":           true,
+	"attribution":       true,
+	"created_by":        true,
+	"tiger:county":      true,
+	"tiger:tlid":        true,
+	"tiger:upload_uuid": true,
+}
+
 // Tag is a key+value item attached to osm nodes, ways and relations.
 type Tag struct {
 	Key   string `xml:"k,attr"`
@@ -38,6 +54,17 @@ func (ts Tags) Map() map[string]string {
 	return result
 }
 
+// AnyInteresting will return true if there is at last one interesting tag.
+func (ts Tags) AnyInteresting() bool {
+	for _, t := range ts {
+		if !UninterestingTags[t.Key] {
+			return true
+		}
+	}
+
+	return false
+}
+
 // MarshalJSON allows the tags to be marshalled as a key/value object,
 // as defined by the overpass osmjson.
 func (ts Tags) MarshalJSON() ([]byte, error) {

tag_test.go

@@ -6,6 +6,44 @@ import (
 	"testing"
 )
 
+func TestTags_AnyInteresting(t *testing.T) {
+	cases := []struct {
+		name        string
+		tags        Tags
+		interesting bool
+	}{
+		{
+			name: "has interesting",
+			tags: Tags{
+				{Key: "building", Value: "yes"},
+			},
+			interesting: true,
+		},
+		{
+			name:        "no tags",
+			tags:        Tags{},
+			interesting: false,
+		},
+		{
+			name: "no interesting tags",
+			tags: Tags{
+				{Key: "source", Value: "whatever"},
+				{Key: "history", Value: "lots"},
+			},
+			interesting: false,
+		},
+	}
+
+	for _, tc := range cases {
+		t.Run(tc.name, func(t *testing.T) {
+			v := tc.tags.AnyInteresting()
+			if v != tc.interesting {
+				t.Errorf("incorrect interesting: %v != %v", v, tc.interesting)
+			}
+		})
+	}
+}
+
 func TestTags_MarshalJSON(t *testing.T) {
 	data, err := Tags{}.MarshalJSON()
 	if err != nil {