Merge branch 'develop' into prototype/snowflake

* develop: (21 commits)
  Remove branching imports and always import from typing_extensions (#4699)
  Add type annotations for media (#4706)
  Components adjustments (#4694)
  Type annotations for type_util (#4704)
  Add type annotations for utils (#4703)
  Argument types for iframe (#4707)
  Add type annotations for write (#4686)
  Add type annotations for doc_string (#4690)
  Add type annotations for progress (#4688)
  Add type annotations for exception (#4681)
  Add type annotations for plotly_chart (#4684)
  Wrap Markdown text when there's no word break (#4696)
  Add type annotations for __init__.py (#4687)
  Make typing-extensions and unconditional dependency (#4697)
  Add type annotations for balloons (#4679)
  Add type annotations for empty (#4680)
  Add type annotations for json (#4682)
  Add type annotations for layouts (#4683)
  Add type annotations for snow (#4685)
  Import Final from typing or typing_extensions depending on the Python version (#4692)
  ...

frontend/package.json

@@ -1,6 +1,6 @@
 {
   "name": "streamlit-browser",
-  "version": "1.8.1",
+  "version": "1.9.0",
   "private": true,
   "homepage": "./",
   "scripts": {

frontend/src/components/elements/Spinner/__snapshots__/Spinner.test.tsx.snap

@@ -1,3 +1,3 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
-exports[`Spinner component renders without crashing 1`] = `"<div class=\\"css-yprxax-StyledSpinnerContainer e17lx80j0\\"><div class=\\"css-yu1mjb-ThemedStyledSpinner e17lx80j1 \\"></div><div data-testid=\\"stMarkdownContainer\\" class=\\"css-1o5mqjl-StyledStreamlitMarkdown e16nr0p33\\"><p>Loading...</p></div></div>"`;
+exports[`Spinner component renders without crashing 1`] = `"<div class=\\"css-yprxax-StyledSpinnerContainer e17lx80j0\\"><div class=\\"css-yu1mjb-ThemedStyledSpinner e17lx80j1 \\"></div><div data-testid=\\"stMarkdownContainer\\" class=\\"css-8npnmo-StyledStreamlitMarkdown e16nr0p33\\"><p>Loading...</p></div></div>"`;

frontend/src/components/shared/Radio/Radio.tsx

@@ -120,6 +120,8 @@ class Radio extends React.PureComponent<Props, State> {
                 },
                 RadioMarkOuter: {
                   style: ({ $checked }: { $checked: boolean }) => ({
+                    width: "1rem",
+                    height: "1rem",
                     backgroundColor:
                       $checked && !disabled
                         ? colors.primary
@@ -128,8 +130,8 @@ class Radio extends React.PureComponent<Props, State> {
                 },
                 RadioMarkInner: {
                   style: ({ $checked }: { $checked: boolean }) => ({
-                    height: $checked ? "6px" : "16px",
-                    width: $checked ? "6px" : "16px",
+                    height: $checked ? "6px" : ".75rem",
+                    width: $checked ? "6px" : ".75rem",
                   }),
                 },
                 Label: {

frontend/src/components/shared/StreamlitMarkdown/styled-components.ts

@@ -35,6 +35,10 @@ export const StyledStreamlitMarkdown = styled.div<
     color: theme.colors.linkText,
   },
 
+  p: {
+    wordWrap: "break-word",
+  },
+
   li: {
     margin: "0.2em 0 0.2em 1.2em",
     padding: "0 0 0 0.6em",

frontend/src/components/widgets/Checkbox/Checkbox.tsx

@@ -152,6 +152,8 @@ class Checkbox extends React.PureComponent<Props, State> {
                 borderTopRightRadius: radii.md,
                 borderBottomLeftRadius: radii.md,
                 borderBottomRightRadius: radii.md,
+                display: "flex",
+                alignItems: "center",
               }),
             },
             Checkmark: {
@@ -167,6 +169,8 @@ class Checkbox extends React.PureComponent<Props, State> {
 
                 return {
                   outline: 0,
+                  width: "1rem",
+                  height: "1rem",
                   boxShadow:
                     $isFocusVisible && $checked
                       ? `0 0 0 0.2rem ${transparentize(colors.primary, 0.5)}`

frontend/src/theme/globalStyles.ts

@@ -150,8 +150,7 @@ export const globalStyles = (theme: Theme): any => css`
     padding: 1.25rem 0 1rem 0;
     margin: 0;
 
-    // Set to 1.4 so it looks nice when wrapped.
-    line-height: 1.4;
+    line-height: 1.2;
   }
 
   h2 {
@@ -165,8 +164,7 @@ export const globalStyles = (theme: Theme): any => css`
     padding: 1rem 0 1rem 0;
     margin: 0;
 
-    // Set to 1.4 so it looks nice when wrapped.
-    line-height: 1.4;
+    line-height: 1.2;
   }
 
   h3 {
@@ -180,8 +178,7 @@ export const globalStyles = (theme: Theme): any => css`
     padding: 0.5rem 0 1rem 0;
     margin: 0;
 
-    // Set to 1.4 so it looks nice when wrapped.
-    line-height: 1.4;
+    line-height: 1.2;
   }
 
   h4 {
@@ -190,7 +187,7 @@ export const globalStyles = (theme: Theme): any => css`
     color: ${theme.colors.headingColor};
     padding: 0.75rem 0 1rem 0;
     margin: 0;
-    line-height: 1.4;
+    line-height: 1.2;
   }
 
   h5 {
@@ -199,7 +196,7 @@ export const globalStyles = (theme: Theme): any => css`
     color: ${theme.colors.headingColor};
     padding: 0 0 1rem 0;
     margin: 0;
-    line-height: 1.4;
+    line-height: 1.2;
   }
 
   h6 {
@@ -208,7 +205,7 @@ export const globalStyles = (theme: Theme): any => css`
     color: ${theme.colors.headingColor};
     padding: 0 0 1rem 0;
     margin: 0;
-    line-height: 1.4;
+    line-height: 1.2;
   }
 
   // Abbreviations

lib/Pipfile

@@ -62,5 +62,5 @@ validators = "*"
 # Without watchdog, we fallback to a polling file watcher to check for app changes.
 watchdog = {version = "*", markers = "platform_system != 'Darwin'"}
 gitpython = "!=3.1.19"
-typing-extensions = { version = "*", markers = "python_version < '3.8'" }
+typing-extensions = "*"
 semver = "*"

lib/setup.py

@@ -34,7 +34,7 @@
     )
     sys.exit(exit_msg)
 
-VERSION = "1.8.1"  # PEP-440
+VERSION = "1.9.0"  # PEP-440
 
 NAME = "streamlit"
 

lib/streamlit/__init__.py

@@ -53,9 +53,9 @@
 # Give the package a version.
 from importlib_metadata import version as _version
 
-__version__ = _version("streamlit")
+__version__: str = _version("streamlit")
 
-from typing import NoReturn
+from typing import Any, Dict, Iterator, List, NoReturn
 import contextlib as _contextlib
 import sys as _sys
 import threading as _threading
@@ -89,10 +89,10 @@
 # This is set to True inside cli._main_run(), and is False otherwise.
 # If False, we should assume that DeltaGenerator functions are effectively
 # no-ops, and adapt gracefully.
-_is_running_with_streamlit = False
+_is_running_with_streamlit: bool = False
 
 
-def _update_logger():
+def _update_logger() -> None:
     _logger.set_log_level(_config.get_option("logger.level").upper())
     _logger.update_formatter()
     _logger.init_tornado_logs()
@@ -206,7 +206,7 @@ def _update_logger():
 beta_columns = _main.beta_columns
 
 
-def set_option(key: str, value) -> None:
+def set_option(key: str, value: Any) -> None:
     """Set config option.
 
     Currently, only the following config options can be set within the script itself:
@@ -228,7 +228,12 @@ def set_option(key: str, value) -> None:
         The new value to assign to this config option.
 
     """
-    opt = _config._config_options_template[key]
+    try:
+        opt = _config._config_options_template[key]
+    except KeyError as ke:
+        raise StreamlitAPIException(
+            "Unrecognized config option: {key}".format(key=key)
+        ) from ke
     if opt.scriptable:
         _config.set_option(key, value)
         return
@@ -240,7 +245,7 @@ def set_option(key: str, value) -> None:
     )
 
 
-def experimental_show(*args):
+def experimental_show(*args: Any) -> None:
     """Write arguments and *argument names* to your app for debugging purposes.
 
     Show() has similar properties to write():
@@ -306,12 +311,21 @@ def experimental_show(*args):
             markdown("**%s**" % escaped)
             write(args[idx])
 
-    except Exception:
+    except Exception as raised_exc:
         _, exc, exc_tb = _sys.exc_info()
+        if exc is None:
+            # Presumably, exc should never be None, but it is typed as
+            # Optional, and I don't know the internals of sys.exc_info() well
+            # enough to just use a cast here. Hence, the runtime check.
+            raise RuntimeError(
+                "Unexpected state: exc was None. If you see this message, "
+                "please create an issue at "
+                "https://github.com/streamlit/streamlit/issues"
+            ) from raised_exc
         exception(exc)
 
 
-def experimental_get_query_params():
+def experimental_get_query_params() -> Dict[str, List[str]]:
     """Return the query parameters that is currently showing in the browser's URL bar.
 
     Returns
@@ -337,11 +351,11 @@ def experimental_get_query_params():
     """
     ctx = _get_script_run_ctx()
     if ctx is None:
-        return ""
+        return {}
     return _parse.parse_qs(ctx.query_string)
 
 
-def experimental_set_query_params(**query_params):
+def experimental_set_query_params(**query_params: Any) -> None:
     """Set the query parameters that are shown in the browser's URL bar.
 
     Parameters
@@ -372,7 +386,7 @@ def experimental_set_query_params(**query_params):
 
 
 @_contextlib.contextmanager
-def spinner(text: str = "In progress..."):
+def spinner(text: str = "In progress...") -> Iterator[None]:
     """Temporarily displays a message while executing a block of code.
 
     Parameters
@@ -432,7 +446,7 @@ def set_message():
                 message.empty()
 
 
-def _transparent_write(*args):
+def _transparent_write(*args: Any) -> Any:
     """This is just st.write, but returns the arguments you passed to it."""
     write(*args)
     if len(args) == 1:
@@ -443,7 +457,7 @@ def _transparent_write(*args):
 # We want to show a warning when the user runs a Streamlit script without
 # 'streamlit run', but we need to make sure the warning appears only once no
 # matter how many times __init__ gets loaded.
-_use_warning_has_been_displayed = False
+_use_warning_has_been_displayed: bool = False
 
 
 def _maybe_print_use_warning() -> None:

lib/streamlit/elements/balloons.py

@@ -12,14 +12,16 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-from typing import cast
+from typing import cast, TYPE_CHECKING
 
-import streamlit
 from streamlit.proto.Balloons_pb2 import Balloons as BalloonsProto
 
+if TYPE_CHECKING:
+    from streamlit.delta_generator import DeltaGenerator
+
 
 class BalloonsMixin:
-    def balloons(self):
+    def balloons(self) -> "DeltaGenerator":
         """Draw celebratory balloons.
 
         Example
@@ -31,9 +33,10 @@ def balloons(self):
         """
         balloons_proto = BalloonsProto()
         balloons_proto.show = True
-        return self.dg._enqueue("balloons", balloons_proto)
+        dg = self.dg._enqueue("balloons", balloons_proto)
+        return cast("DeltaGenerator", dg)
 
     @property
-    def dg(self) -> "streamlit.delta_generator.DeltaGenerator":
+    def dg(self) -> "DeltaGenerator":
         """Get our DeltaGenerator."""
-        return cast("streamlit.delta_generator.DeltaGenerator", self)
+        return cast("DeltaGenerator", self)

lib/streamlit/elements/button.py

@@ -13,24 +13,24 @@
 # limitations under the License.
 
 import io
-from streamlit.scriptrunner import ScriptRunContext, get_script_run_ctx
-
-from streamlit.type_util import Key, to_key
 from typing import cast, Optional, Union, BinaryIO, TextIO
-from typing_extensions import Final
 from textwrap import dedent
+from typing_extensions import Final
 
 import streamlit
 from streamlit.errors import StreamlitAPIException
 from streamlit.proto.Button_pb2 import Button as ButtonProto
 from streamlit.in_memory_file_manager import in_memory_file_manager
 from streamlit.proto.DownloadButton_pb2 import DownloadButton as DownloadButtonProto
+from streamlit.scriptrunner import ScriptRunContext, get_script_run_ctx
 from streamlit.state import (
     register_widget,
     WidgetArgs,
     WidgetCallback,
     WidgetKwargs,
 )
+from streamlit.type_util import Key, to_key
+
 from .form import current_form_id, is_in_form
 from .utils import check_callback_rules, check_session_state_rules
 

lib/streamlit/elements/doc_string.py

@@ -15,27 +15,30 @@
 """Allows us to create and absorb changes (aka Deltas) to elements."""
 
 import inspect
+from typing import Any, cast, TYPE_CHECKING
+from typing_extensions import Final
 
-from typing import cast
-
-import streamlit
 from streamlit.proto.DocString_pb2 import DocString as DocStringProto
 from streamlit.logger import get_logger
 
-LOGGER = get_logger(__name__)
+if TYPE_CHECKING:
+    from streamlit.delta_generator import DeltaGenerator
+
+
+LOGGER: Final = get_logger(__name__)
 
 
-CONFUSING_STREAMLIT_MODULES = (
+CONFUSING_STREAMLIT_MODULES: Final = (
     "streamlit.echo",
     "streamlit.delta_generator",
     "streamlit.legacy_caching.caching",
 )
 
-CONFUSING_STREAMLIT_SIG_PREFIXES = ("(element, ",)
+CONFUSING_STREAMLIT_SIG_PREFIXES: Final = ("(element, ",)
 
 
 class HelpMixin:
-    def help(self, obj):
+    def help(self, obj: Any) -> "DeltaGenerator":
         """Display object's doc string, nicely formatted.
 
         Displays the doc string for this object.
@@ -61,15 +64,18 @@ def help(self, obj):
         """
         doc_string_proto = DocStringProto()
         _marshall(doc_string_proto, obj)
-        return self.dg._enqueue("doc_string", doc_string_proto)
+        return cast(
+            "DeltaGenerator",
+            self.dg._enqueue("doc_string", doc_string_proto),
+        )
 
     @property
-    def dg(self) -> "streamlit.delta_generator.DeltaGenerator":
+    def dg(self) -> "DeltaGenerator":
         """Get our DeltaGenerator."""
-        return cast("streamlit.delta_generator.DeltaGenerator", self)
+        return cast("DeltaGenerator", self)
 
 
-def _marshall(doc_string_proto, obj):
+def _marshall(doc_string_proto: DocStringProto, obj: Any) -> None:
     """Construct a DocString object.
 
     See DeltaGenerator.help for docs.