Fuse

This tool can be used to join the features, or parts of features, in two input vectors. Unlike similar vector overlay tools, Fuse is not a true Boolean operator. Importantly, the Fuse tool will maintain all interior boundaries when combining features. If there is a need to remove interior boundaries between features, you should use the Union instead. Therefore, the Fuse is similar to ArcGIS's Union tool.

See Also:

Scripting:

The following is an example of a Python script that uses this tool:

wd = pluginHost.getWorkingDirectory()
inputFile1 = wd + "input2.shp"
inputFile2 = wd + "input2.shp"
outputFile = wd + "output.shp"
args = [inputFile1, inputFile2 outputFile]
pluginHost.runPlugin("Fuse", args, False)

This is a Groovy script also using this tool:

def wd = pluginHost.getWorkingDirectory()
def inputFile1 = wd + "input1.shp"
def inputFile2 = wd + "input2.shp"
def outputFile = wd + "output.shp"
String[] args = [inputFile1, inputFile2, outputFile]
pluginHost.runPlugin("Fuse", args, false)

Credits: