BUG: Mercator A defined only for lat_0 = 0

[kdpenner]

Raises CRSError if latitude_natural_origin != 0.

• Closes Transformer with MercatorAConversion with lat/lon of natural origin returns ProjError #1089
• Tests added
• Fully documented, including history.rst for all changes and api/*.rst for new API

[codecov]

Codecov Report

Merging #1095 (563b2fe) into main (ab942b2) will increase coverage by 0.00%.
The diff coverage is 100.00%.

❗ Current head 563b2fe differs from pull request most recent head 783b1ad. Consider uploading reports for the commit 783b1ad to get more accurate results

@@           Coverage Diff           @@
##             main    #1095   +/-   ##
=======================================
  Coverage   96.14%   96.15%           
=======================================
  Files          20       20           
  Lines        1792     1794    +2     
=======================================
+ Hits         1723     1725    +2     
  Misses         69       69           

Impacted Files	Coverage Δ
pyproj/crs/coordinate_operation.py	99.14% <100.00%> (+0.01%)	⬆️

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[snowman2]

Thanks @kdpenner 👍

• Thoughts on adding a reference link in the docstrings?
• Mind adding a test checking the CRSError is raised to ensure this behavior remains consistent in the future?

def test_mercator_a_non_zero_lat_0():
    with pytest.raises(CRSError):
         ProjectedCRS(conversion=MercatorAConversion(1, 2, 3, 4))

• Also, once you are complete, would you like to squash your commits? Or would you mind if I squash on merge?

[kdpenner]

You're welcome!

Thoughts on adding a reference link in the docstrings?

I'm on board, I'll add one in the incoming (squashed) commit.

Mind adding a test checking the CRSError is raised to ensure this behavior remains consistent in the future?

A test is here:

pyproj/test/crs/test_crs_coordinate_operation.py

Line 334 in 563b2fe

def test_mercator_a_operation__invalid_lat0():

I like the explicit keyword argument (vs. (1, 2, 3, 4)) because latitude_natural_origin != 0 is the unsupported call.

Also, once you are complete, would you like to squash your commits? Or would you mind if I squash on merge?

Will squash.

[snowman2]

Thanks @kdpenner 👍