Composer – The requested package exists as but these are rejected by your constraint

The version constraint "1.0" is interpreted internally as "1.0.0.0-stable" version.

But the only version available is:

antoineb1/smoney_bundle[dev-master].

So you could change the specified version to either one of the following depending on what version is suitable for you:

• 1.0.* (which is seen by composer as >=1.0.0.0-dev <1.1.0.0-dev — probably won’t work because there obviously aren’t any versions in that package)
• dev-master
• dev-master#<hash>
• @dev
• etc.

See the composer schema for reference.