MPL drawer CU1 gate is inconsistent with other drawers

[sumitpuri]

Information

• Qiskit Terra version: 0.11.0
• Python version: 3.7
• Operating system: Mac OS 10.15.1

What is the current behavior?

circuit = QuantumCircuit(2)
theta = numpy.pi/2
circuit.cu1(theta,0,1)
circuit.draw()

Output-

q_0: |0>─■─────
         │pi/2 
q_1: |0>─■─────

However, mpl shows fine-

Steps to reproduce the problem

Paste the above code in Jupyter notebook and run.

What is the expected behavior?

The text drawer should show up like this-

q_0: |0>─────■──────
        ┌────┴─────┐
q_1: |0>┤ U1(pi/2) ├
        └──────────┘

Suggested solutions

Fix is provided below in the PR by making changes in qiskit/visualization/text.py

[ajavadia]

Thanks for bringing up the inconsistency. This was supposed to have been fixed via #1957 (and PR #2254). Seems like a regression.

However note that the text drawer is correct here. CU1 is a symmetric gate and thus a typical notation to signify this is to draw control/target the same. So mpl drawer should be fixed.

[sumitpuri]

Got it, I will fix the MPL Drawer.

[sumitpuri]

@ajavadia Does this look right?

Also, I am already working on a different bug and have a PR open. Whenever I push my changes for this bug, the changes get tied to that already opened PR. How can I push so that it creates a new PR related to this bug?

[1ucian0]

The results looks correct!

About the git issue, I think the problem is that you have to put different fixes in different branches (all from master). You can create different PRs from them.