Add documentation_style to with short and full options

tests/expectations/doclength_short.c

@@ -0,0 +1,14 @@
+#include <stdarg.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdlib.h>
+
+/**
+ * The root of all evil.
+ */
+void root(void);
+
+/**
+ * A little above the root, and a lot more visible, with a run-on sentence
+ */
+void trunk(void);

tests/expectations/doclength_short.compat.c

@@ -0,0 +1,22 @@
+#include <stdarg.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdlib.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif // __cplusplus
+
+/**
+ * The root of all evil.
+ */
+void root(void);
+
+/**
+ * A little above the root, and a lot more visible, with a run-on sentence
+ */
+void trunk(void);
+
+#ifdef __cplusplus
+} // extern "C"
+#endif // __cplusplus

tests/expectations/doclength_short.cpp

@@ -0,0 +1,15 @@
+#include <cstdarg>
+#include <cstdint>
+#include <cstdlib>
+#include <ostream>
+#include <new>
+
+extern "C" {
+
+/// The root of all evil.
+void root();
+
+/// A little above the root, and a lot more visible, with a run-on sentence
+void trunk();
+
+} // extern "C"

tests/expectations/doclength_short.pyx

@@ -0,0 +1,20 @@
+from libc.stdint cimport int8_t, int16_t, int32_t, int64_t, intptr_t
+from libc.stdint cimport uint8_t, uint16_t, uint32_t, uint64_t, uintptr_t
+cdef extern from *:
+  ctypedef bint bool
+  ctypedef struct va_list
+
+cdef extern from *:
+
+  # The root of all evil.
+  #
+  # But at least it contains some more documentation as someone would expect
+  # from a simple test case like this. Though, this shouldn't appear in the
+  # output.
+  void root();
+
+  # A little above the root, and a lot more visible, with a run-on sentence
+  # to test going over the first line.
+  #
+  # Still not here, though.
+  void trunk();

tests/rust/doclength_short.rs

@@ -0,0 +1,16 @@
+/// The root of all evil.
+///
+/// But at least it contains some more documentation as someone would expect
+/// from a simple test case like this. Though, this shouldn't appear in the
+/// output.
+#[no_mangle]
+pub extern "C" fn root() {
+}
+
+/// A little above the root, and a lot more visible, with a run-on sentence
+/// to test going over the first line.
+///
+/// Still not here, though.
+#[no_mangle]
+pub extern "C" fn trunk() {
+}

tests/rust/doclength_short.toml

@@ -0,0 +1 @@
+documentation_length = "short"

tests/tests.rs

@@ -208,6 +208,10 @@ fn run_compile_test(
 
         cbindgen_outputs.insert(cbindgen_output);
 
+        if env::var_os("CBINDGEN_TEST_NO_COMPILE").is_some() {
+            return;
+        }
+
         compile(
             &generated_file,
             &tests_path,