From 10f095de65229367696ca25165447ea251d98fdc Mon Sep 17 00:00:00 2001
From: Martin Wicke <577277+martinwicke@users.noreply.github.com>
Date: Mon, 24 Apr 2023 12:10:06 -0700
Subject: [PATCH 1/5] Add test cases for self-documenting variables

This is preparation for supporting https://docs.python.org/3/whatsnew/3.8.html#f-strings-support-for-self-documenting-expressions-and-debugging.
---
 testdata/ast/fstring.in | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/testdata/ast/fstring.in b/testdata/ast/fstring.in
index 684eb21..19fcb78 100644
--- a/testdata/ast/fstring.in
+++ b/testdata/ast/fstring.in
@@ -50,3 +50,7 @@ f"""
   j
  )
 """
+
+f'k='
+
+f'k= i'

From 752fc9ca0f8f94f5424617c6c81542b9bef7b0f0 Mon Sep 17 00:00:00 2001
From: Martin Wicke <577277+martinwicke@users.noreply.github.com>
Date: Mon, 24 Apr 2023 12:10:34 -0700
Subject: [PATCH 2/5] Fix typo

---
 testdata/ast/fstring.in | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/testdata/ast/fstring.in b/testdata/ast/fstring.in
index 19fcb78..e4d4c7b 100644
--- a/testdata/ast/fstring.in
+++ b/testdata/ast/fstring.in
@@ -53,4 +53,4 @@ f"""
 
 f'k='
 
-f'k= i'
+f'k= l'

From 384c7711ec1615da037e07eb1622b404f68ec3bb Mon Sep 17 00:00:00 2001
From: Martin Wicke <577277+martinwicke@users.noreply.github.com>
Date: Mon, 24 Apr 2023 13:00:33 -0700
Subject: [PATCH 3/5] Self-documenting variables in f-strings

Eat a = after a variable in an f-string. This is already encoded in the structure of the JoinedStr so we shouldn't have to remember it.
---
 pasta/base/annotate.py | 14 +++++++++-----
 1 file changed, 9 insertions(+), 5 deletions(-)

diff --git a/pasta/base/annotate.py b/pasta/base/annotate.py
index c3b6429..08d5917 100644
--- a/pasta/base/annotate.py
+++ b/pasta/base/annotate.py
@@ -1490,11 +1490,15 @@ def check_slice_includes_step(self, node):
     def visit_FormattedValue(self, node):
       self.visit(node.value)
       if node.conversion != -1:
-        self.attr(
-            node,
-            'conversion', [self.ws, '!', chr(node.conversion)],
-            deps=('conversion',),
-            default='!%c' % node.conversion)
+        # If we have a self-documenting token, eat the '='.
+        if self.tokens.peek_non_whitespace().src == '=':
+          self.token('=')
+        else:
+          self.attr(
+              node,
+              'conversion', [self.ws, '!', chr(node.conversion)],
+              deps=('conversion',),
+              default='!%c' % node.conversion)
       if node.format_spec:
         self.attr(
             node, 'format_spec_prefix', [self.ws, ':', self.ws], default=':')

From 721900685dcd2e1dc69e0a7f95e5a441ffe561a2 Mon Sep 17 00:00:00 2001
From: Martin Wicke <577277+martinwicke@users.noreply.github.com>
Date: Wed, 17 May 2023 10:54:37 -0700
Subject: [PATCH 4/5] Use optional_token, allow ! with =

Also add link to docs.
---
 pasta/base/annotate.py | 16 +++++++---------
 1 file changed, 7 insertions(+), 9 deletions(-)

diff --git a/pasta/base/annotate.py b/pasta/base/annotate.py
index 08d5917..718efbf 100644
--- a/pasta/base/annotate.py
+++ b/pasta/base/annotate.py
@@ -1490,15 +1490,13 @@ def check_slice_includes_step(self, node):
     def visit_FormattedValue(self, node):
       self.visit(node.value)
       if node.conversion != -1:
-        # If we have a self-documenting token, eat the '='.
-        if self.tokens.peek_non_whitespace().src == '=':
-          self.token('=')
-        else:
-          self.attr(
-              node,
-              'conversion', [self.ws, '!', chr(node.conversion)],
-              deps=('conversion',),
-              default='!%c' % node.conversion)
+        # If we have a self-documenting token, eat the '=' (see https://docs.python.org/3/whatsnew/3.8.html#f-strings-support-for-self-documenting-expressions-and-debugging)
+        self.optional_token(node, 'self_documenting', '=')
+        self.attr(
+            node,
+            'conversion', [self.ws, '!', chr(node.conversion)],
+            deps=('conversion',),
+            default='!%c' % node.conversion)
       if node.format_spec:
         self.attr(
             node, 'format_spec_prefix', [self.ws, ':', self.ws], default=':')

From 103cda1fb90d9f16ef66460a8b2dc698302908c2 Mon Sep 17 00:00:00 2001
From: Martin Wicke <577277+martinwicke@users.noreply.github.com>
Date: Wed, 17 May 2023 10:56:36 -0700
Subject: [PATCH 5/5] Fix {x=} test cases and add more

---
 testdata/ast/fstring.in | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/testdata/ast/fstring.in b/testdata/ast/fstring.in
index e4d4c7b..5cc6fa5 100644
--- a/testdata/ast/fstring.in
+++ b/testdata/ast/fstring.in
@@ -51,6 +51,10 @@ f"""
  )
 """
 
-f'k='
+f'{k=}'
 
-f'k= l'
+f'{l=!s}'
+
+f'{m  =:.3f}'
+
+f'{n=} l'