I think that one has the same original problem where instead of using PREFIX incorrectly, now it uses LOCALBASE incorrectly (installs the current stuff into LOCALBASE).

Use the correct path for everything, rather than subbing it at the end (which was fragile for any later groupings).

I'm a bit confused by this. If we install too $FOO/bin but check for presence in $BAR/bin, how is that not broken anyway when ever $FOO != $BAR ?

How about adding

.if empty(${QT_DIST})
QT_PREFIX=${LOCALBASE}
.else
QT_PREFIX=${PREFIX}
.endif

and using ${QT_PREFIX} for the foo_PATH=. This feels slightly more correct to me. But I might be off :)

In D12666#263120, @tcberner wrote:

I'm a bit confused by this. If we install too $FOO/bin but check for presence in $BAR/bin, how is that not broken anyway when ever $FOO != $BAR ?

PREFIX (where this port is being installed into) can't be assumed to equal LOCALBASE (where previously installed ports exist). Currently, when PREFIX is changed, QT-based ports break.

In D12666#263145, @tcberner wrote:
How about adding
.if empty(${QT_DIST})
QT_PREFIX=${LOCALBASE}
.else
QT_PREFIX=${PREFIX}
.endif
and using ${QT_PREFIX} for the foo_PATH=. This feels slightly more correct to me. But I might be off :)

I believe ${QT_DIST} is only for ports that are actually QT modules. This patch deals with any port that uses QT modules.

In D12666#263147, @adamw wrote:
In D12666#263145, @tcberner wrote:
How about adding
.if empty(${QT_DIST})
QT_PREFIX=${LOCALBASE}
.else
QT_PREFIX=${PREFIX}
.endif
and using ${QT_PREFIX} for the foo_PATH=. This feels slightly more correct to me. But I might be off :)
I believe ${QT_DIST} is only for ports that are actually QT modules. This patch deals with any port that uses QT modules.

Exactly, but QT_DIST ports also use Qt modules, and as they are basically one big split up thing, they should look in PREFIX and not LOCALBASE for the stuff. The component paths you modify are not only used by other ports.

A port may expect to find Qt in $LOCALBASE, but a part of Qt (i.e. a $QT_BASE setting port) needs to look for it in $PREFIX as Qt-parts cannot be installed into different paths than other parts.

In D12666#263168, @tcberner wrote:

Exactly, but QT_DIST ports also use Qt modules, and as they are basically one big split up thing, they should look in PREFIX and not LOCALBASE for the stuff. The component paths you modify are not only used by other ports.

A port may expect to find Qt in $LOCALBASE, but a part of Qt (i.e. a $QT_BASE setting port) needs to look for it in $PREFIX as Qt-parts cannot be installed into different paths than other parts.

When you make install PREFIX=/foo, the ONLY thing that should be in /foo is the current port. Separating $PREFIX and $LOCALBASE isn't about coming up with a usable system. It's about installing this port to a specific location. Maybe it's for testing. Maybe's it's separate packaging. Either way, ports always install into $PREFIX, and always look for dependencies in $LOCALBASE. Dependencies are NEVER supposed to be checked in $PREFIX.