shell session: allow continuation without marker for PowerShell

Fixes #2262

2 files changed, 136 insertions, 4 deletions

diff --git a/pygments/lexers/shell.py b/pygments/lexers/shell.py
index be74a040..e25274eb 100644
--- a/pygments/lexers/shell.py
+++ b/pygments/lexers/shell.py
@@ -154,6 +154,7 @@ class ShellSessionBaseLexer(Lexer):
     .. versionadded:: 2.1
     """
 
+    _bare_continuation = False
     _venv = re.compile(r'^(\([^)]*\))(\s*)')
 
     def get_tokens_unprocessed(self, text):
@@ -172,10 +173,10 @@ class ShellSessionBaseLexer(Lexer):
                 venv = venv_match.group(1)
                 venv_whitespace = venv_match.group(2)
                 insertions.append((len(curcode),
-                    [(0, Generic.Prompt.VirtualEnv, venv)]))
+                                   [(0, Generic.Prompt.VirtualEnv, venv)]))
                 if venv_whitespace:
                     insertions.append((len(curcode),
-                        [(0, Text, venv_whitespace)]))
+                                       [(0, Text, venv_whitespace)]))
                 line = line[venv_match.end():]
 
             m = self._ps1rgx.match(line)
@@ -193,11 +194,17 @@ class ShellSessionBaseLexer(Lexer):
             elif backslash_continuation:
                 if line.startswith(self._ps2):
                     insertions.append((len(curcode),
-                                    [(0, Generic.Prompt, line[:len(self._ps2)])]))
+                                       [(0, Generic.Prompt,
+                                         line[:len(self._ps2)])]))
                     curcode += line[len(self._ps2):]
                 else:
                     curcode += line
                 backslash_continuation = curcode.endswith('\\\n')
+            elif self._bare_continuation and line.startswith(self._ps2):
+                insertions.append((len(curcode),
+                                   [(0, Generic.Prompt,
+                                     line[:len(self._ps2)])]))
+                curcode += line[len(self._ps2):]
             else:
                 if insertions:
                     toks = innerlexer.get_tokens_unprocessed(curcode)
@@ -774,8 +781,9 @@ class PowerShellSessionLexer(ShellSessionBaseLexer):
     mimetypes = []
 
     _innerLexerCls = PowerShellLexer
+    _bare_continuation = True
     _ps1rgx = re.compile(r'^((?:\[[^]]+\]: )?PS[^>]*> ?)(.*\n?)')
-    _ps2 = '>> '
+    _ps2 = '> '
 
 
 class FishShellLexer(RegexLexer):
diff --git a/tests/snippets/pwsh-session/test_continuation.txt b/tests/snippets/pwsh-session/test_continuation.txt
new file mode 100644
index 00000000..4735d369
--- /dev/null
+++ b/tests/snippets/pwsh-session/test_continuation.txt
@@ -0,0 +1,124 @@
+---input---
+PS> python -m doctest `
+> -o DONT_ACCEPT_TRUE_FOR_1 `
+> -o ELLIPSIS options.txt
+
+PS>  $Params = @{
+>     Height = 50
+>     Width  = 50
+>     Depth  = 50
+>     Name   = 'My Widget'
+>     ID     = '10dbe43f-0269-48b8-96cb-447a755add55'
+> }
+
+
+PS>  ls |
+> grep "python"
+
+---tokens---
+'PS> '        Generic.Prompt
+'python'      Name
+' '           Text
+'-m'          Name
+' '           Text
+'doctest'     Name
+' '           Text
+'`'           Punctuation
+'\n'          Text
+
+'> '          Generic.Prompt
+'-o'          Name
+' '           Text
+'DONT_ACCEPT_TRUE_FOR_1' Name
+' '           Text
+'`'           Punctuation
+'\n'          Text
+
+'> '          Generic.Prompt
+'-o'          Name
+' '           Text
+'ELLIPSIS'    Name
+' '           Text
+'options'     Name
+'.'           Punctuation
+'txt'         Name
+'\n'          Text
+
+'\n'          Generic.Output
+
+'PS> '        Generic.Prompt
+' '           Text
+'$Params'     Name.Variable
+' '           Text
+'='           Punctuation
+' '           Text
+'@'           Punctuation
+'{'           Punctuation
+'\n'          Text
+
+'> '          Generic.Prompt
+'    '        Text
+'Height'      Name
+' '           Text
+'='           Punctuation
+' '           Text
+'50'          Name
+'\n'          Text
+
+'> '          Generic.Prompt
+'    '        Text
+'Width'       Name
+'  '          Text
+'='           Punctuation
+' '           Text
+'50'          Name
+'\n'          Text
+
+'> '          Generic.Prompt
+'    '        Text
+'Depth'       Name
+'  '          Text
+'='           Punctuation
+' '           Text
+'50'          Name
+'\n'          Text
+
+'> '          Generic.Prompt
+'    '        Text
+'Name'        Name
+'   '         Text
+'='           Punctuation
+' '           Text
+"'My Widget'" Literal.String.Single
+'\n'          Text
+
+'> '          Generic.Prompt
+'    '        Text
+'ID'          Name
+'     '       Text
+'='           Punctuation
+' '           Text
+"'10dbe43f-0269-48b8-96cb-447a755add55'" Literal.String.Single
+'\n'          Text
+
+'> '          Generic.Prompt
+'}'           Punctuation
+'\n'          Text
+
+'\n'          Generic.Output
+
+'\n'          Generic.Output
+
+'PS> '        Generic.Prompt
+' '           Text
+'ls '         Name.Builtin
+'|'           Punctuation
+'\n'          Text
+
+'> '          Generic.Prompt
+'grep'        Name
+' '           Text
+'"'           Literal.String.Double
+'python'      Literal.String.Double
+'"'           Literal.String.Double
+'\n'          Text