Got a working version of index builder that seems to do what is needed.

tests/test_project.py

@@ -11,6 +11,7 @@ from nwdummy import DummyMain
 from nw.config          import Config
 from nw.project.project import NWProject
 from nw.project.item    import NWItem
+from nw.project.index   import NWIndex
 from nw.enum            import nwItemClass
 
 theConf = Config()
@@ -60,3 +61,39 @@ def testProjectNewRoot(nwTempProj,nwRef):
     assert theProject.saveProject()
     assert cmpFiles(projFile, refFile, [2])
     assert not theProject.projChanged
+
+@pytest.mark.project
+def testIndexScanThis(nwTempProj):
+    projFile = path.join(nwTempProj,"nwProject.nwx")
+    assert theProject.openProject(projFile)
+
+    theIndex = NWIndex(theProject,theMain)
+    tHandle  = "31489056e0916"
+
+    isValid, theBits, thePos = theIndex.scanThis("tag: this, and this")
+    assert not isValid
+
+    isValid, theBits, thePos = theIndex.scanThis("@:")
+    assert not isValid
+
+    isValid, theBits, thePos = theIndex.scanThis("@a:")
+    assert isValid
+    assert str(theBits) == "['@a']"
+    assert str(thePos)  == "[0]"
+
+    isValid, theBits, thePos = theIndex.scanThis("@a:b")
+    assert isValid
+    assert str(theBits) == "['@a', 'b']"
+    assert str(thePos)  == "[0, 3]"
+
+    isValid, theBits, thePos = theIndex.scanThis("@a:b,c,d")
+    assert isValid
+    assert str(theBits) == "['@a', 'b', 'c', 'd']"
+    assert str(thePos)  == "[0, 3, 5, 7]"
+
+    isValid, theBits, thePos = theIndex.scanThis("@tag: this, and this")
+    assert isValid
+    assert str(theBits) == "['@tag', 'this', 'and this']"
+    assert str(thePos)  == "[0, 6, 12]"
+
+    # assert False