This commit adds support for theme composition and inheritance in Hugo.
With this, it helps thinking about a theme as a set of ordered components:
```toml
theme = ["my-shortcodes", "base-theme", "hyde"]
```
The theme definition example above in `config.toml` creates a theme with the 3 components with presedence from left to right.
So, Hugo will, for any given file, data entry etc., look first in the project, and then in `my-shortcode`, `base-theme` and lastly `hyde`.
Hugo uses two different algorithms to merge the filesystems, depending on the file type:
* For `i18n` and `data` files, Hugo merges deeply using the translation id and data key inside the files.
* For `static`, `layouts` (templates) and `archetypes` files, these are merged on file level. So the left-most file will be chosen.
The name used in the `theme` definition above must match a folder in `/your-site/themes`, e.g. `/your-site/themes/my-shortcodes`. There are plans to improve on this and get a URL scheme so this can be resolved automatically.
Also note that a component that is part of a theme can have its own configuration file, e.g. `config.toml`. There are currently some restrictions to what a theme component can configure:
* `params` (global and per language)
* `menu` (global and per language)
* `outputformats` and `mediatypes`
The same rules apply here: The left-most param/menu etc. with the same ID will win. There are some hidden and experimental namespace support in the above, which we will work to improve in the future, but theme authors are encouraged to create their own namespaces to avoid naming conflicts.
A final note: Themes/components can also have a `theme` definition in their `config.toml` and similar, which is the "inheritance" part of this commit's title. This is currently not supported by the Hugo theme site. We will have to wait for some "auto dependency" feature to be implemented for that to happen, but this can be a powerful feature if you want to create your own theme-variant based on others.
Fixes#4460Fixes#4450
Add a configuration option "noreferrerLinks". When set to "true" the "HTML_NOREFERRER_LINKS" flag is being passed to Blackfriday. Thereby all *absolute* links will get a "noreferrer" value for their "rel" attribute.
See #4722
Add a configuration option "nofollowLinks". When set to "true" the "HTML_NOFOLLOW_LINKS" flag is being passed to Blackfriday. Thereby all *absolute* links will get a "nofollow" value for the "rel" attribute.
Fixes#4722
This bug was introduced in Hugo 0.40. It is when you use the `<!--more-->` summary marker.
Note that this affects the word stats only. The related `PlainWords`, `Plain`, `Content` all return correct values.
Fixes#4675Fixes#4682
This resolves some surprising behaviour when reading other pages' content from shortcodes. Before this commit, that behaviour was undefined. Note that this has never been an issue from regular templates.
It will still not be possible to get **the current shortcode's page's rendered content**. That would have impressed Einstein.
The new and well defined rules are:
* `.Page.Content` from a shortcode will be empty. The related `.Page.Truncated` `.Page.Summary`, `.Page.WordCount`, `.Page.ReadingTime`, `.Page.Plain` and `.Page.PlainWords` will also have empty values.
* For _other pages_ (retrieved via `.Page.Site.GetPage`, `.Site.Pages` etc.) the `.Content` is there to use as you please as long as you don't have infinite content recursion in your shortcode/content setup. See below.
* `.Page.TableOfContents` is good to go (but does not support shortcodes in headlines; this is unchanged)
If you get into a situation of infinite recursion, the `.Content` will be empty. Run `hugo -v` for more information.
Fixes#4632Fixes#4653Fixes#4655
A sample config:
```toml
defaultContentLanguage = "en"
defaultContentLanguageInSubdir = true
[Languages]
[Languages.en]
weight = 10
title = "In English"
languageName = "English"
contentDir = "content/english"
[Languages.nn]
weight = 20
title = "På Norsk"
languageName = "Norsk"
contentDir = "content/norwegian"
```
The value of `contentDir` can be any valid path, even absolute path references. The only restriction is that the content dirs cannot overlap.
The content files will be assigned a language by
1. The placement: `content/norwegian/post/my-post.md` will be read as Norwegian content.
2. The filename: `content/english/post/my-post.nn.md` will be read as Norwegian even if it lives in the English content folder.
The content directories will be merged into a big virtual filesystem with one simple rule: The most specific language file will win.
This means that if both `content/norwegian/post/my-post.md` and `content/english/post/my-post.nn.md` exists, they will be considered duplicates and the version inside `content/norwegian` will win.
Note that translations will be automatically assigned by Hugo by the content file's relative placement, so `content/norwegian/post/my-post.md` will be a translation of `content/english/post/my-post.md`.
If this does not work for you, you can connect the translations together by setting a `translationKey` in the content files' front matter.
Fixes#4523Fixes#4552Fixes#4553
This allows a `config.toml` (or `yaml`, ´yml`, or `json`) in the theme to set:
1) `params` (but cannot override params in project. Will also get its own "namespace", i.e. `{{ .Site.Params.mytheme.my_param }}` will be the same as `{{ .Site.Params.my_param }}` providing that the main project does not define a param with that key.
2) `menu` -- but cannot redefine/add menus in the project. Must create its own menus with its own identifiers.
3) `languages` -- only `params` and `menu`. Same rules as above.
4) **new** `outputFormats`
5) **new** `mediaTypes`
This should help with the "theme portability" issue and people having to copy and paste lots of setting into their projects.
Fixes#4490
This commit makes it possible to extract the date from the content filename. Also, the filenames in these cases will make for very poor permalinks, so we will also use the remaining part as the page `slug` if that value is not set in front matter.
This should make it easier to move content from Jekyll to Hugo.
To enable, put this in your `config.toml`:
```toml
[frontmatter]
date = [":filename", ":default"]
```
This commit is also a spring cleaning of how the different dates are configured in Hugo. Hugo will check for dates following the configuration from left to right, starting with `:filename` etc.
So, if you want to use the `file modification time`, this can be a good configuration:
```toml
[frontmatter]
date = [ "date",":fileModTime", ":default"]
lastmod = ["lastmod" ,":fileModTime", ":default"]
```
The current `:default` values for the different dates are
```toml
[frontmatter]
date = ["date","publishDate", "lastmod"]
lastmod = ["lastmod", "date","publishDate"]
publishDate = ["publishDate", "date"]
expiryDate = ["expiryDate"]
```
The above will now be the same as:
```toml
[frontmatter]
date = [":default"]
lastmod = [":default"]
publishDate = [":default"]
expiryDate = [":default"]
```
Note:
* We have some built-in aliases to the above: lastmod => modified, publishDate => pubdate, published and expiryDate => unpublishdate.
* If you want a new configuration for, say, `date`, you can provide only that line, and the rest will be preserved.
* All the keywords to the right that does not start with a ":" maps to front matter parameters, and can be any date param (e.g. `myCustomDateParam`).
* The keywords to the left are the **4 predefined dates in Hugo**, i.e. they are constant values.
* The current "special date handlers" are `:fileModTime` and `:filename`. We will soon add `:git` to that list.
Fixes#285Closes#3310Closes#3762Closes#4340
This means that you can do something ala:
```html
{{ if ge .Hugo.Version "0.36" }}Reasonable new Hugo version!{{ end }}
```
The intented use is feature toggling, but please note that it will take some time and Hugo versions until this can be trusted. It does not work in older Hugo versions.
Fixes#4443
This fixes some issues with language params handling by separating params from configuration values per language.
This means that you can now do this:
```toml
[languages]
[languages.en]
languageName = "English"
weight = 1
title = "My Cool Site"
[languages.en.params]
myParam = "Hi!"
```
This is not a breaking change, but the above is a less suprising way of configuring custom params.
It also fixes some hard-to-debug corner-cases in multilingual sites.
Fixes#4356Fixes#4352
This commit adds a new config setting:
```toml
disableLanguages = ["fr"]
```
If this is a multilingual site:
* No site for the French language will be created
* French content pages will be ignored/not read
* The French language configuration (menus etc.) will also be ignored
This makes it possible to start translating new languages and turn it on when you're happy etc.
Fixes#4297Fixed#4329
