Add a sympy 1.5 run for CircleCI (#164)

This needs some extra sanitization rules in nbval

Author: eric-wieser

.circleci/config.yml

@@ -9,6 +9,10 @@ defaults: &defaults
         command: |
           sudo pip install -r test_requirements.txt
           sudo pip install -e .
+          if [ -n "$PIP_EXTRA_INSTALLATION" ]; then
+            # deliberately not quoted
+            sudo pip install $PIP_EXTRA_INSTALLATION
+          fi
           sudo pip check
     - run:
         name: Test
@@ -28,6 +32,13 @@ defaults: &defaults
         path: test-reports
 
 jobs:
+  "python-3.7-sympy-1.5":
+    <<: *defaults
+    environment:
+      PIP_EXTRA_INSTALLATION: sympy==1.5
+    docker:
+      - image: circleci/python:3.7
+
   "python-3.7":
     <<: *defaults
     docker:
@@ -53,3 +64,4 @@ workflows:
       - "python-3.6"
       - "python-3.5"
       - "python-2.7"
+      - "python-3.7-sympy-1.5"

test/.nbval_sanitize.cfg

@@ -10,3 +10,29 @@ replace: $
 
 regex: \s*\$\s*
 replace: $
+
+[sympy printing changes]
+regex: \\left \(
+replace: \\left(
+regex: \\right \)
+replace: \\right)
+regex: \\left \[
+replace: \\left[
+regex: \\right \]
+replace: \\right]
+
+# note hacks to avoid trailing spaces which editors may trim
+regex: , \\quad( )
+replace: , \ \1
+
+# sympy 1.5 seems to reorder a few additions compared to 1.3
+regex: \\begin\{matrix}- \\frac\{\\sqrt\{2}}\{4} \+ \\frac\{1}\{2}\\end\{matrix}
+replace: \\begin{matrix}\\frac{1}{2} - \\frac{\\sqrt{2}}{4}\\end{matrix}
+regex: =( +)- \\frac\{\\sqrt\{2}}\{4} \+ \\frac\{1}\{2}(?=\$| \\end\{equation\*})
+replace: =\1\\frac{1}{2} - \\frac{\\sqrt{2}}{4}
+
+regex: \{- \\left\( e_\{E}\\cdot e_\{B}\\right\) \^\{2} \+ 1\}
+replace: {1 - \\left( e_{E}\\cdot e_{B}\\right) ^{2}}
+
+regex: eu\.ev_r = -1/2 \+ 1/2(?=\n)
+replace: eu.ev_r = 1/2 - 1/2