docs: Minor updates to Plugin Writer's Guide

boiler.md:
    Update meson command to avoid warning.

states.md:
    Clarify that a sink element accepting only one buffer only happens when paused.
    Link text duplicated normal text.

args.md:
    A valid range is between values, not between ranges.  Reword for clarity.

testapp.md:
    Clarify linking refers to the pipeline, not build time compilation and linking.

Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/5939>

subprojects/gst-docs/markdown/plugin-development/basics/args.md

@@ -96,8 +96,8 @@ applications will use these properties and will display a
 user-controllable widget with which these properties can be changed.
 This means that - for the property to be as user-friendly as possible -
 you should be as exact as possible in the definition of the property.
-Not only in defining ranges in between which valid properties can be
-located (for integers, floats, etc.), but also in using very descriptive
+Not only in defining ranges of valid property values (for integers,
+floats, etc.), but also in using very descriptive
 (better yet: internationalized) strings in the definition of the
 property, and if possible using enums and flags instead of integers. The
 GObject documentation describes these in a very complete way, but below,

subprojects/gst-docs/markdown/plugin-development/basics/boiler.md

@@ -96,7 +96,7 @@ The last command creates two files: `gstmyfilter.c` and `gstmyfilter.h`.
 > It is recommended that you create a copy of the `gst-plugin` directory
 > before continuing.
 
-Now one needs to run `meson build` from the parent directory to bootstrap the
+Now one needs to run `meson setup build` from the parent directory to bootstrap the
 build environment. After that, the project can be built and installed using the
 well known `ninja -C build` commands.
 

subprojects/gst-docs/markdown/plugin-development/basics/states.md

@@ -38,8 +38,8 @@ should *not* be allocated in this state.
 
 `GST_STATE_PAUSED` is the state in which an element is ready to accept
 and handle data. For most elements this state is the same as PLAYING.
-The only exception to this rule are sink elements. Sink elements only
-accept one single buffer of data and then block. At this point the
+The only exception to this rule are sink elements. Paused sink elements
+only accept one buffer of data and then block. At this point the
 pipeline is 'prerolled' and ready to render data immediately.
 
 `GST_STATE_PLAYING` is the highest state that an element can be in. For
@@ -51,9 +51,9 @@ card or render video pictures to an image sink.
 
 ## Managing filter state
 
-If at all possible, your element should derive from one of the new base
-classes ([Pre-made base classes](plugin-development/element-types/base-classes.md)). There are
-ready-made general purpose base classes for different types of sources,
+If at all possible, your element should derive from one of the
+[pre-made base classes](plugin-development/element-types/base-classes.md).
+These are ready-made general purpose base classes for different types of sources,
 sinks and filter/transformation elements. In addition to those,
 specialised base classes exist for audio and video elements and others.
 

subprojects/gst-docs/markdown/plugin-development/basics/testapp.md

@@ -4,8 +4,8 @@ title: Building a Test Application
 
 # Building a Test Application
 
-Often, you will want to test your newly written plugin in an as small
-setting as possible. Usually, `gst-launch-1.0` is a good first step at
+Often, you will want to test your newly written plugin in as small
+a setting as possible. Usually, `gst-launch-1.0` is a good first step at
 testing a plugin. If you have not installed your plugin in a directory
 that GStreamer searches, then you will need to set the plugin path.
 Either set GST\_PLUGIN\_PATH to the directory containing your plugin, or
@@ -38,7 +38,7 @@ a `fakesink` element at the end of the pipeline to dump your data to the
 stdout (in order to do this, set the `dump` property to TRUE). Lastly,
 you can use valgrind to check for memory errors.
 
-During linking, your test application can use filtered caps as a way to
+During pipeline linking, your test application can use filtered caps as a way to
 drive a specific type of data to or from your element. This is a very
 simple and effective way of checking multiple types of input and output
 in your element.