We are currently solving the following issue within our repository. Here is the issue text:
--- BEGIN ISSUE ---
--short has no effect when `poetry version` is passed a new version
<!--
  Hi there! Thank you for discovering and submitting an issue.

  Before you submit this; let's make sure of a few things.
  Please make sure the following boxes are ticked if they are correct.
  If not, please try and fulfill these first.
-->

<!-- Checked checkbox should look like this: [x] -->
- [x] I am on the [latest](https://github.com/python-poetry/poetry/releases/latest) Poetry version.
- [x] I have searched the [issues](https://github.com/python-poetry/poetry/issues) of this repo and believe that this is not a duplicate.
- [x] If an exception occurs when executing a command, I executed it again in debug mode (`-vvv` option).

<!--
  Once those are done, if you're able to fill in the following list with your information,
  it'd be very helpful to whoever handles the issue.
-->

- **OS version and name**: Ubuntu 16.04
- **Poetry version**: 1.1.4
- **Link of a [Gist](https://gist.github.com/) with the contents of your pyproject.toml file**: n/a

## Issue
<!-- Now feel free to write your issue, but please be descriptive! Thanks again 🙌 ❤️ -->

Hi there!

Assuming the current version of a project is 0.1.0, this is what happens when trying to update to the next patch version with the `--short` option:

```console
$ poetry version patch --short
Bumping version from 0.1.0 to 0.1.1
```

Instead, I would like this to be output (only the new version number):

```console
$ poetry version patch --short
0.1.1
```

My use case is scripting: if the user only provides a bump rule to my script, I'd like to be able to easily parse the new version computed by poetry so that I can e.g. create a new git tag easily, and so on.

Thanks!

--- END ISSUE ---

Below are some code segments, each from a relevant file. One or more of these files may contain bugs.
--- BEGIN FILES ---
Path: `poetry/console/commands/version.py`
Content:
```
1 from cleo import argument
2 from cleo import option
3 
4 from .command import Command
5 
6 
7 class VersionCommand(Command):
8 
9     name = "version"
10     description = (
11         "Shows the version of the project or bumps it when a valid "
12         "bump rule is provided."
13     )
14 
15     arguments = [
16         argument(
17             "version",
18             "The version number or the rule to update the version.",
19             optional=True,
20         )
21     ]
22     options = [option("short", "s", "Output the version number only")]
23 
24     help = """\
25 The version command shows the current version of the project or bumps the version of
26 the project and writes the new version back to <comment>pyproject.toml</> if a valid
27 bump rule is provided.
28 
29 The new version should ideally be a valid semver string or a valid bump rule:
30 patch, minor, major, prepatch, preminor, premajor, prerelease.
31 """
32 
33     RESERVED = {
34         "major",
35         "minor",
36         "patch",
37         "premajor",
38         "preminor",
39         "prepatch",
40         "prerelease",
41     }
42 
43     def handle(self):
44         version = self.argument("version")
45 
46         if version:
47             version = self.increment_version(
48                 self.poetry.package.pretty_version, version
49             )
50 
51             self.line(
52                 "Bumping version from <b>{}</> to <fg=green>{}</>".format(
53                     self.poetry.package.pretty_version, version
54                 )
55             )
56 
57             content = self.poetry.file.read()
58             poetry_content = content["tool"]["poetry"]
59             poetry_content["version"] = version.text
60 
61             self.poetry.file.write(content)
62         else:
63             if self.option("short"):
64                 self.line("{}".format(self.poetry.package.pretty_version))
65             else:
66                 self.line(
67                     "<comment>{}</> <info>{}</>".format(
68                         self.poetry.package.name, self.poetry.package.pretty_version
69                     )
70                 )
71 
72     def increment_version(self, version, rule):
73         from poetry.core.semver import Version
74 
75         try:
76             version = Version.parse(version)
77         except ValueError:
78             raise ValueError("The project's version doesn't seem to follow semver")
79 
80         if rule in {"major", "premajor"}:
81             new = version.next_major
82             if rule == "premajor":
83                 new = new.first_prerelease
84         elif rule in {"minor", "preminor"}:
85             new = version.next_minor
86             if rule == "preminor":
87                 new = new.first_prerelease
88         elif rule in {"patch", "prepatch"}:
89             new = version.next_patch
90             if rule == "prepatch":
91                 new = new.first_prerelease
92         elif rule == "prerelease":
93             if version.is_prerelease():
94                 pre = version.prerelease
95                 new_prerelease = int(pre[1]) + 1
96                 new = Version.parse(
97                     "{}.{}.{}-{}".format(
98                         version.major,
99                         version.minor,
100                         version.patch,
101                         ".".join([pre[0], str(new_prerelease)]),
102                     )
103                 )
104             else:
105                 new = version.next_patch.first_prerelease
106         else:
107             new = Version.parse(rule)
108 
109         return new
110
```
--- END FILES ---

Please first localize the bug based on the issue statement, and then generate a patch according to the `git diff` format fenced by three backticks.

Here is an example:

```diff
diff --git a/examples/server_async.py b/examples/server_async.py
--- a/examples/server_async.py
+++ b/examples/server_async.py
@@ -313,4 +313,4 @@
 
 
 if __name__ == "__main__":
-    asyncio.run(run_async_server("."), debug=True)
+    asyncio.run(run_async_server(), debug=True)
diff --git a/examples/server_sync.py b/examples/server_sync.py
--- a/examples/server_sync.py
+++ b/examples/server_sync.py
@@ -313,5 +313,5 @@
 
 
 if __name__ == "__main__":
-    server = run_sync_server(".")
+    server = run_sync_server()
     server.shutdown()

```

diff --git a/poetry/console/commands/version.py b/poetry/console/commands/version.py
--- a/poetry/console/commands/version.py
+++ b/poetry/console/commands/version.py
@@ -48,11 +48,14 @@
                 self.poetry.package.pretty_version, version
             )
 
-            self.line(
-                "Bumping version from <b>{}</> to <fg=green>{}</>".format(
-                    self.poetry.package.pretty_version, version
+            if self.option("short"):
+                self.line("{}".format(version))
+            else:
+                self.line(
+                    "Bumping version from <b>{}</> to <fg=green>{}</>".format(
+                        self.poetry.package.pretty_version, version
+                    )
                 )
-            )
 
             content = self.poetry.file.read()
             poetry_content = content["tool"]["poetry"]

{"golden_diff": "diff --git a/poetry/console/commands/version.py b/poetry/console/commands/version.py\n--- a/poetry/console/commands/version.py\n+++ b/poetry/console/commands/version.py\n@@ -48,11 +48,14 @@\n                 self.poetry.package.pretty_version, version\n             )\n \n-            self.line(\n-                \"Bumping version from <b>{}</> to <fg=green>{}</>\".format(\n-                    self.poetry.package.pretty_version, version\n+            if self.option(\"short\"):\n+                self.line(\"{}\".format(version))\n+            else:\n+                self.line(\n+                    \"Bumping version from <b>{}</> to <fg=green>{}</>\".format(\n+                        self.poetry.package.pretty_version, version\n+                    )\n                 )\n-            )\n \n             content = self.poetry.file.read()\n             poetry_content = content[\"tool\"][\"poetry\"]\n", "issue": "--short has no effect when `poetry version` is passed a new version\n<!--\r\n  Hi there! Thank you for discovering and submitting an issue.\r\n\r\n  Before you submit this; let's make sure of a few things.\r\n  Please make sure the following boxes are ticked if they are correct.\r\n  If not, please try and fulfill these first.\r\n-->\r\n\r\n<!-- Checked checkbox should look like this: [x] -->\r\n- [x] I am on the [latest](https://github.com/python-poetry/poetry/releases/latest) Poetry version.\r\n- [x] I have searched the [issues](https://github.com/python-poetry/poetry/issues) of this repo and believe that this is not a duplicate.\r\n- [x] If an exception occurs when executing a command, I executed it again in debug mode (`-vvv` option).\r\n\r\n<!--\r\n  Once those are done, if you're able to fill in the following list with your information,\r\n  it'd be very helpful to whoever handles the issue.\r\n-->\r\n\r\n- **OS version and name**: Ubuntu 16.04\r\n- **Poetry version**: 1.1.4\r\n- **Link of a [Gist](https://gist.github.com/) with the contents of your pyproject.toml file**: n/a\r\n\r\n## Issue\r\n<!-- Now feel free to write your issue, but please be descriptive! Thanks again \ud83d\ude4c \u2764\ufe0f -->\r\n\r\nHi there!\r\n\r\nAssuming the current version of a project is 0.1.0, this is what happens when trying to update to the next patch version with the `--short` option:\r\n\r\n```console\r\n$ poetry version patch --short\r\nBumping version from 0.1.0 to 0.1.1\r\n```\r\n\r\nInstead, I would like this to be output (only the new version number):\r\n\r\n```console\r\n$ poetry version patch --short\r\n0.1.1\r\n```\r\n\r\nMy use case is scripting: if the user only provides a bump rule to my script, I'd like to be able to easily parse the new version computed by poetry so that I can e.g. create a new git tag easily, and so on.\r\n\r\nThanks!\n", "before_files": [{"content": "from cleo import argument\nfrom cleo import option\n\nfrom .command import Command\n\n\nclass VersionCommand(Command):\n\n    name = \"version\"\n    description = (\n        \"Shows the version of the project or bumps it when a valid \"\n        \"bump rule is provided.\"\n    )\n\n    arguments = [\n        argument(\n            \"version\",\n            \"The version number or the rule to update the version.\",\n            optional=True,\n        )\n    ]\n    options = [option(\"short\", \"s\", \"Output the version number only\")]\n\n    help = \"\"\"\\\nThe version command shows the current version of the project or bumps the version of\nthe project and writes the new version back to <comment>pyproject.toml</> if a valid\nbump rule is provided.\n\nThe new version should ideally be a valid semver string or a valid bump rule:\npatch, minor, major, prepatch, preminor, premajor, prerelease.\n\"\"\"\n\n    RESERVED = {\n        \"major\",\n        \"minor\",\n        \"patch\",\n        \"premajor\",\n        \"preminor\",\n        \"prepatch\",\n        \"prerelease\",\n    }\n\n    def handle(self):\n        version = self.argument(\"version\")\n\n        if version:\n            version = self.increment_version(\n                self.poetry.package.pretty_version, version\n            )\n\n            self.line(\n                \"Bumping version from <b>{}</> to <fg=green>{}</>\".format(\n                    self.poetry.package.pretty_version, version\n                )\n            )\n\n            content = self.poetry.file.read()\n            poetry_content = content[\"tool\"][\"poetry\"]\n            poetry_content[\"version\"] = version.text\n\n            self.poetry.file.write(content)\n        else:\n            if self.option(\"short\"):\n                self.line(\"{}\".format(self.poetry.package.pretty_version))\n            else:\n                self.line(\n                    \"<comment>{}</> <info>{}</>\".format(\n                        self.poetry.package.name, self.poetry.package.pretty_version\n                    )\n                )\n\n    def increment_version(self, version, rule):\n        from poetry.core.semver import Version\n\n        try:\n            version = Version.parse(version)\n        except ValueError:\n            raise ValueError(\"The project's version doesn't seem to follow semver\")\n\n        if rule in {\"major\", \"premajor\"}:\n            new = version.next_major\n            if rule == \"premajor\":\n                new = new.first_prerelease\n        elif rule in {\"minor\", \"preminor\"}:\n            new = version.next_minor\n            if rule == \"preminor\":\n                new = new.first_prerelease\n        elif rule in {\"patch\", \"prepatch\"}:\n            new = version.next_patch\n            if rule == \"prepatch\":\n                new = new.first_prerelease\n        elif rule == \"prerelease\":\n            if version.is_prerelease():\n                pre = version.prerelease\n                new_prerelease = int(pre[1]) + 1\n                new = Version.parse(\n                    \"{}.{}.{}-{}\".format(\n                        version.major,\n                        version.minor,\n                        version.patch,\n                        \".\".join([pre[0], str(new_prerelease)]),\n                    )\n                )\n            else:\n                new = version.next_patch.first_prerelease\n        else:\n            new = Version.parse(rule)\n\n        return new\n", "path": "poetry/console/commands/version.py"}], "after_files": [{"content": "from cleo import argument\nfrom cleo import option\n\nfrom .command import Command\n\n\nclass VersionCommand(Command):\n\n    name = \"version\"\n    description = (\n        \"Shows the version of the project or bumps it when a valid \"\n        \"bump rule is provided.\"\n    )\n\n    arguments = [\n        argument(\n            \"version\",\n            \"The version number or the rule to update the version.\",\n            optional=True,\n        )\n    ]\n    options = [option(\"short\", \"s\", \"Output the version number only\")]\n\n    help = \"\"\"\\\nThe version command shows the current version of the project or bumps the version of\nthe project and writes the new version back to <comment>pyproject.toml</> if a valid\nbump rule is provided.\n\nThe new version should ideally be a valid semver string or a valid bump rule:\npatch, minor, major, prepatch, preminor, premajor, prerelease.\n\"\"\"\n\n    RESERVED = {\n        \"major\",\n        \"minor\",\n        \"patch\",\n        \"premajor\",\n        \"preminor\",\n        \"prepatch\",\n        \"prerelease\",\n    }\n\n    def handle(self):\n        version = self.argument(\"version\")\n\n        if version:\n            version = self.increment_version(\n                self.poetry.package.pretty_version, version\n            )\n\n            if self.option(\"short\"):\n                self.line(\"{}\".format(version))\n            else:\n                self.line(\n                    \"Bumping version from <b>{}</> to <fg=green>{}</>\".format(\n                        self.poetry.package.pretty_version, version\n                    )\n                )\n\n            content = self.poetry.file.read()\n            poetry_content = content[\"tool\"][\"poetry\"]\n            poetry_content[\"version\"] = version.text\n\n            self.poetry.file.write(content)\n        else:\n            if self.option(\"short\"):\n                self.line(\"{}\".format(self.poetry.package.pretty_version))\n            else:\n                self.line(\n                    \"<comment>{}</> <info>{}</>\".format(\n                        self.poetry.package.name, self.poetry.package.pretty_version\n                    )\n                )\n\n    def increment_version(self, version, rule):\n        from poetry.core.semver import Version\n\n        try:\n            version = Version.parse(version)\n        except ValueError:\n            raise ValueError(\"The project's version doesn't seem to follow semver\")\n\n        if rule in {\"major\", \"premajor\"}:\n            new = version.next_major\n            if rule == \"premajor\":\n                new = new.first_prerelease\n        elif rule in {\"minor\", \"preminor\"}:\n            new = version.next_minor\n            if rule == \"preminor\":\n                new = new.first_prerelease\n        elif rule in {\"patch\", \"prepatch\"}:\n            new = version.next_patch\n            if rule == \"prepatch\":\n                new = new.first_prerelease\n        elif rule == \"prerelease\":\n            if version.is_prerelease():\n                pre = version.prerelease\n                new_prerelease = int(pre[1]) + 1\n                new = Version.parse(\n                    \"{}.{}.{}-{}\".format(\n                        version.major,\n                        version.minor,\n                        version.patch,\n                        \".\".join([pre[0], str(new_prerelease)]),\n                    )\n                )\n            else:\n                new = version.next_patch.first_prerelease\n        else:\n            new = Version.parse(rule)\n\n        return new\n", "path": "poetry/console/commands/version.py"}]}